OFLOXACIN: 3,062 Adverse Event Reports & Safety Profile

DESCRIPTION Ofloxacin tablets are a synthetic broad-spectrum antimicrobial agent for oral administration. Chemically, ofloxacin, USP, a fluorinated carboxyquinolone, is the racemate, (±)-9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-7 H -pyrido[1,2,3- de ]-1,4-benzoxazine-6-carboxylic acid. The chemical structure is: C 18 H 20 FN 3 O 4 M.W.

361.4 Ofloxacin, USP is an off-white to pale yellow crystalline powder. The molecule exists as a zwitterion at the pH conditions in the small intestine. The relative solubility characteristics of ofloxacin USP at room temperature, as defined by USP nomenclature, indicate that ofloxacin, USP is considered to be soluble in aqueous solutions with pH between 2 and 5. It is sparingly to slightly soluble in aqueous solutions with pH 7 (solubility falls to 4 mg/mL) and freely soluble in aqueous solutions with pH above 9. Ofloxacin USP has the potential to form stable coordination compounds with many metal ions. This in vitro chelation potential has the following formation order: Fe +3 > Al +3 > Cu +2 > Ni +2 > Pb +2 > Zn +2 > Mg +2 > Ca +2 > Ba +2 Ofloxacin tablets, USP contain the following inactive ingredients: lactose monohydrate, pregelatinized maize starch, hydroxy propyl methyl cellulose, talc, magnesium stearate, polyethylene glycol, sodium starch glycolate, and titanium dioxide. Additionally, the 200 mg and 400 mg tablets contain iron oxide yellow. The imprinting ink for 200 mg, 300 mg and 400 mg strength contains FD&C blue #1, isopropyl alcohol, Nbutyl alcohol, propylene glycol, shellac and titanium dioxide. ofloxacin-fig1-structure1

INDICATIONS AND USAGE To reduce the development of drug-resistant bacteria and maintain the effectiveness of ofloxacin tablets, USP and other antibacterial drugs, ofloxacin tablets, USP should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy. Ofloxacin tablets, USP are indicated for the treatment of adults with mild to moderate infections (unless otherwise indicated) caused by susceptible strains of the designated microorganisms in the infections listed below. Please see DOSAGE AND ADMINISTRATION for specific recommendations.

Acute Bacterial

Exacerbations of Chronic Bronchitis (ABECB) due to Haemophilus influenzae or Streptococcus pneumoniae . Because fluoroquinolones, including ofloxacin, have been associated with serious adverse reactions (see Warnings ), - and for some patients ABECB is self-limiting, reserve ofloxacin for treatment of ABECB in patients who have no alternative treatment options . Community-Acquired Pneumonia due to Haemophilus influenzae or Streptococcus pneumoniae .

Uncomplicated

Skin and Skin Structure Infections due to methicillin-susceptible Staphylococcus aureus, Streptococcus pyogenes, or Proteus mirabilis. Acute, Uncomplicated Urethral and Cervical Gonorrhea due to Neisseria gonorrhoeae (see WARNINGS ).

Nongonococcal

Urethritis and Cervicitis due to Chlamydia trachomatis (see WARNINGS ).

Mixed

Infections of the Urethra and Cervix due to Chlamydia trachomatis and Neisseria gonorrhoeae (see WARNINGS ).

Acute Pelvic Inflammatory

Disease (including severe infection) due to Chlamydia trachomatis and/or Neisseria gonorrhoeae (see WARNINGS ). NOTE: If anaerobic microorganisms are suspected of contributing to the infection, appropriate therapy for anaerobic pathogens should be administered.

Uncomplicated

Cystitis due to Citrobacter diversus, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, or Pseudomonas aeruginosa. Because fluoroquinolones, including ofloxacin, have been associated with serious adverse reactions (see WARNINGS ), and for some patients uncomplicated cystitis is self-limiting, reserve ofloxacin for treatment of uncomplicated cystitis in patients who have no alternative treatment options.

Complicated Urinary Tract

Infections due to Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Citrobacter diversus,* or Pseudomonas aeruginosa.* Prostatitis due to Escherichia coli. * = Although treatment of infections due to this organism in this organ system demonstrated a clinically significant outcome, efficacy was studied in fewer than 10 patients. Appropriate culture and susceptibility tests should be performed before treatment in order to isolate and identify organisms causing the infection and to determine their susceptibility to ofloxacin, USP. Therapy with ofloxacin, USP may be initiated before results of these tests are known; once results become available, appropriate therapy should be continued. As with other drugs in this class, some strains of Pseudomonas aeruginosa may develop resistance fairly rapidly during treatment with ofloxacin, USP. Culture and susceptibility testing performed periodically during therapy will provide information not only on the therapeutic effect of the antimicrobial agent but also on the possible emergence of bacterial resistance.

DOSAGE AND ADMINISTRATION Otitis Externa The recommended dosage regimen for the treatment of otitis externa is: For pediatric patients (from 6 months to 13 years old): Five drops (0.25 mL, 0.75 mg ofloxacin) instilled into the affected ear once daily for seven days. For patients 13 years and older: Ten drops (0.5 mL, 1.5 mg ofloxacin) instilled into the affected ear once daily for seven days. The solution should be warmed by holding the bottle in the hand for one or two minutes to avoid dizziness which may result from the instillation of a cold solution. The patient should lie with the affected ear upward, and then the drops should be instilled. This position should be maintained for five minutes to facilitate penetration of the drops into the ear canal. Repeat, if necessary, for the opposite ear.

Acute Otitis

Media in Pediatric Patients with Tympanostomy Tubes The recommended dosage regimen for the treatment of acute otitis media in pediatric patients (from one to 12 years old) with tympanostomy tubes is:

• Five drops (0.25 mL, 0.75 mg ofloxacin) instilled into the affected ear twice daily for ten days. The solution should be warmed by holding the bottle in the hand for one or two minutes to avoid dizziness that may result from the instillation of a cold solution. The patient should lie with the affected ear upward, and then the drops should be instilled. The tragus should then be pumped 4 times by pushing inward to facilitate penetration of the drops into the middle ear. This position should be maintained for five minutes. Repeat, if necessary, for the opposite ear.

Chronic Suppurative Otitis

Media with Perforated Tympanic Membranes The recommended dosage regimen for the treatment of chronic suppurative otitis media with perforated tympanic membranes in patients 12 years and older is:

• Ten drops (0.5 mL, 1.5 mg ofloxacin) instilled into the affected ear twice daily for fourteen days. The solution should be warmed by holding the bottle in the hand for one or two minutes to avoid dizziness that may result from the instillation of a cold solution. The patient should lie with the affected ear upward, before instilling the drops. The tragus should then be pumped 4 times by pushing inward to facilitate penetration into the middle ear. This position should be maintained for five minutes. Repeat, if necessary, for the opposite ear.

Otitis Externa

The recommended dosage regimen for the treatment of otitis externa is: For pediatric patients (from 6 months to 13 years old): Five drops (0.25 mL, 0.75 mg ofloxacin) instilled into the affected ear once daily for seven days. For patients 13 years and older: Ten drops (0.5 mL, 1.5 mg ofloxacin) instilled into the affected ear once daily for seven days. The solution should be warmed by holding the bottle in the hand for one or two minutes to avoid dizziness which may result from the instillation of a cold solution. The patient should lie with the affected ear upward, and then the drops should be instilled. This position should be maintained for five minutes to facilitate penetration of the drops into the ear canal. Repeat, if necessary, for the opposite ear.

CONTRAINDICATIONS Ofloxacin Ophthalmic Solution is contraindicated in patients with a history of hypersensitivity to ofloxacin, to other quinolones, or to any of the components in this medication ( see WARNINGS ) .

ADVERSE REACTIONS The following is a compilation of the data for ofloxacin based on clinical experience with both the oral and intravenous formulations. The incidence of drug-related adverse reactions in patients during Phase 2 and 3 clinical trials was 11%. Among patients receiving multiple-dose therapy, 4% discontinued ofloxacin due to adverse experiences. In clinical trials, the following events were considered likely to be drug-related in patients receiving multiple doses of ofloxacin: nausea 3%, insomnia 3%, headache 1%, dizziness 1%, diarrhea 1%, vomiting 1%, rash 1%, pruritus 1%, external genital pruritus in women 1%, vaginitis 1%, dysgeusia 1%. In clinical trials, the most frequently reported adverse events, regardless of relationship to drug, were: nausea 10%, headache 9%, insomnia 7%, external genital pruritus in women 6%, dizziness 5%, vaginitis 5%, diarrhea 4%, vomiting 4%. In clinical trials, the following events, regardless of relationship to drug, occurred in 1 to 3% of patients: abdominal pain and cramps, chest pain, decreased appetite, dry mouth, dysgeusia, fatigue, flatulence, gastrointestinal distress, nervousness, pharyngitis, pruritus, fever, rash, sleep disorders, somnolence, trunk pain, vaginal discharge, visual disturbances, and constipation. Additional events, occurring in clinical trials at a rate of less than 1%, regardless of relationship to drug, were: Body as a Whole: asthenia, chills, malaise, extremity pain, pain, epistaxis Cardiovascular System: cardiac arrest, edema, hypertension, hypotension, palpitations, vasodilation Gastrointestinal System: dyspepsia Genital/Reproductive System: burning, irritation, pain and rash of the female genitalia; dysmenorrhea; menorrhagia; metrorrhagia Musculoskeletal System: arthralgia, myalgia Nervous System: seizures, anxiety, cognitive change, depression, dream abnormality, euphoria, hallucinations, paresthesia, syncope, vertigo, tremor, confusion Nutritional/Metabolic: thirst, weight loss Respiratory System: respiratory arrest, cough, rhinorrhea Skin/Hypersensitivity: angioedema, diaphoresis, urticaria, vasculitis Special Senses: decreased hearing acuity, tinnitus, photophobia Urinary System: dysuria, urinary frequency, urinary retention The following laboratory abnormalities appeared in ≥ 1% of patients receiving multiple doses of ofloxacin. It is not known whether these abnormalities were caused by the drug or the underlying conditions being treated. Hematopoietic: anemia, leukopenia, leukocytosis, neutropenia, neutrophilia, increased band forms, lymphocytopenia, eosinophilia, lymphocytosis, thrombocytopenia, thrombocytosis, elevated ESR Hepatic: elevated: alkaline phosphatase, AST (SGOT), ALT (SGPT)

Serum

Chemistry: hyperglycemia, hypoglycemia, elevated creatinine, elevated BUN Urinary: glucosuria, proteinuria, alkalinuria, hyposthenuria, hematuria, pyuria Postmarketing Adverse Events Additional adverse events, regardless of relationship to drug, reported from worldwide marketing experience with quinolones, including ofloxacin: Clinical Cardiovascular System: cerebral thrombosis, pulmonary edema, tachycardia, hypotension/shock, syncope, torsade de pointes. Endocrine/Metabolic: hyper- or hypoglycemia, especially in diabetic patients on insulin or oral hypoglycemic agents (see PRECAUTIONS , General and Drug Interactions ).

Gastrointestinal

System: hepatic dysfunction including: hepatic necrosis, jaundice (cholestatic or hepatocellular), hepatitis; intestinal perforation; hepatic failure (including fatal cases); pseudomembranous colitis (the onset of pseudomembranous colitis symptoms may occur during or after antimicrobial treatment), GI hemorrhage; hiccough, painful oral mucosa, pyrosis (see WARNINGS ).

Genital/Reproductive

System: vaginal candidiasis Hematopoietic: anemia, including hemolytic and aplastic; hemorrhage, pancytopenia, agranulocytosis, leukopenia, reversible bone marrow depression, thrombocytopenia, thrombotic thrombocytopenic purpura, petechiae, ecchymosis/bruising (see WARNINGS ). Musculoskeletal: tendinitis/rupture; weakness; rhabdomyolysis (see WARNINGS ).

Nervous

System: nightmares; suicidal thoughts or acts, disorientation, psychotic reactions, paranoia; phobia, agitation, restlessness, aggressiveness/hostility, manic reaction, emotional lability; peripheral neuropathy that may be irreversible, ataxia, incoordination; exacerbation of: myasthenia gravis and extrapyramidal disorders; dysphasia, lightheadedness (see WARNINGS and PRECAUTIONS ).

Respiratory

System: dyspnea, bronchospasm, allergic pneumonitis, stridor (see WARNINGS ). Skin/Hypersensitivity: anaphylactic (-toid) reactions/shock; purpura, serum sickness, erythema multiforme/Stevens-Johnson syndrome, erythema nodosum, exfoliative dermatitis, hyperpigmentation, toxic epidermal necrolysis, conjunctivitis, photosensitivity/phototoxicity reaction, vesiculobullous eruption (see WARNINGS and PRECAUTIONS ).

Special

Senses: diplopia, nystagmus, blurred vision, disturbances of: taste, smell, hearing and equilibrium, usually reversible following discontinuation Urinary System: anuria, polyuria, renal calculi, renal failure, interstitial nephritis, hematuria (see WARNINGS and PRECAUTIONS ).

Laboratory

Hematopoietic: prolongation of prothrombin time Serum Chemistry: acidosis, elevation of: serum triglycerides, serum cholesterol, serum potassium, liver function tests including: GGTP, LDH, bilirubin Urinary: albuminuria, candiduria In clinical trials using multiple-dose therapy, ophthalmologic abnormalities, including cataracts and multiple punctate lenticular opacities, have been noted in patients undergoing treatment with other quinolones. The relationship of the drugs to these events is not presently established. CRYSTALLURIA and CYLINDRURIA HAVE BEEN REPORTED with other quinolones.

WARNINGS Disabling and Potentially Irreversible Serious Adverse Reactions Including Tendinitis and Tendon Rupture, Peripheral Neuropathy, and Central Nervous System Effects Fluoroquinolones, including ofloxacin, have been associated with disabling and potentially irreversible serious adverse reactions from different body systems that can occur together in the same patient. Commonly seen adverse reactions include tendinitis, tendon rupture, arthralgia, myalgia, peripheral neuropathy, and central nervous system effects (hallucinations, anxiety, depression, insomnia, severe headaches, and confusion). These reactions can occur within hours to weeks after starting ofloxacin. Patients of any age or without pre-existing risk factors have experienced these adverse reactions (see Warnings ) Discontinue ofloxacin immediately at the first signs or symptoms of any serious adverse reaction. In addition, avoid the use of fluoroquinolones, including ofloxacin, in patients who have experienced any of these serious adverse reactions associated with fluoroquinolones. Tendinitis and Tendon Rupture Fluoroquinolones, including ofloxacin, have been associated with an increased risk of tendinitis and tendon rupture in all ages. This adverse reaction most frequently involves the Achilles tendon, and rupture of the Achilles tendon and has been reported with the rotator cuff (the shoulder), the hand, the biceps, the thumb, and other tendons. Tendinitis or tendon rupture can occur within hours or days of starting ofloxacin, or as long as several months after completion of fluoroquinolone therapy. Tendinitis and tendon rupture can occur bilaterally. The risk of developing fluoroquinolone-associated tendinitis and tendon rupture is increased in patients over 60 years of age, in those taking corticosteroid drugs, and in patients with kidney, heart or lung transplants. Other factors that may independently increase the risk of tendon rupture include strenuous physical activity, renal failure, and previous tendon disorders such as rheumatoid arthritis. Tendinitis and tendon rupture have been reported in patients taking fluoroquinolones who do not have the above risk factors. Discontinue ofloxacin immediately if the patient experiences pain, swelling, inflammation or rupture of a tendon. Avoid fluoroquinolones, including ofloxacin, in patients who have a history of tendon disorders or have experienced tendinitis or tendon rupture (see Adverse Reactions ). Patients should be advised to rest at the first sign of tendinitis or tendon rupture, and to contact their healthcare provider regarding changing to a non-quinolone antimicrobial drug.

Peripheral Neuropathy

Fluoroquinolones, including ofloxacin, have been associated with an increased risk of peripheral neuropathy. Cases of sensory or sensorimotor axonal polyneuropathy affecting small and/or large axons resulting in paresthesias, hypoesthesias, dysesthesias and weakness have been reported in patients receiving fluoroquinolones, including ofloxacin. Symptoms may occur soon after initiation of norfloxacin and may be irreversible in some patients (see WARNINGS ). Discontinue ofloxacin immediately if the patient experiences symptoms of peripheral neuropathy including pain, burning, tingling, numbness, and/or weakness, or other alterations in sensations including light touch, pain, temperature, position sense and vibratory sensation, and/or motor strength in order to minimize the development of an irreversible condition. Avoid fluoroquinolones, including ofloxacin, in patients who have previously experienced peripheral neuropathy (see Adverse Reactions )

Central Nervous System Effects Psychiatric

Adverse Reactions Fluoroquinolones, including ofloxacin, have been associated with an increased risk of psychiatric adverse reactions toxic psychoses or hallucinations; agitation; delirium, confusion, disorientation, or disturbances in attention; nervousness or restlessness, memory impairment. If these reactions occur in patients receiving ofloxacin, the drug should be discontinued and appropriate measures instituted.

Central Nervous System Adverse Reactions

Fluoroquinolones have been associated with an increased risk of seizures (convulsions), increased intracranial pressure (pseudotumor cerebri), lightheadedness, or tremors. The effects of ofloxacin on brain function or on the electrical activity of the brain have not been tested. Therefore, until more information becomes available, ofloxacin, like all other quinolones, should be used with caution in patients with known or suspected CNS disorders, such as severe cerebral arteriosclerosis, epilepsy, and other factors which predispose to seizures (see ADVERSE REACTIONS ). Exacerbation of Myasthenia Gravis Fluoroquinolones, including ofloxacin, have neuromuscular blocking activity and may exacerbate muscle weakness in persons with myasthenia gravis. Postmarketing serious adverse events, including deaths and requirement for ventilatory support, have been associated with fluoroquinolone use in persons with myasthenia gravis. Avoid ofloxacin in patients with known history of myasthenia gravis (see PRECAUTIONS, Information for Patients and ADVERSE REACTIONS, Postmarketing Adverse Events ). THE SAFETY AND EFFICACY OF OFLOXACIN IN PEDIATRIC PATIENTS AND ADOLESCENTS (UNDER THE AGE OF 18 YEARS), PREGNANT WOMEN, AND LACTATING WOMEN HAVE NOT BEEN ESTABLISHED (see PRECAUTIONS, Pediatric Use , Pregnancy , and Nursing Mothers Subsections). In the immature rat, the oral administration of ofloxacin at 5 to 16 times the recommended maximum human dose based on mg/kg or 1 to 3 times based on mg/m 2 increased the incidence and severity of osteochondrosis. The lesions did not regress after 13 weeks of drug withdrawal. Other quinolones also produce similar erosions in the weight-bearing joints and other signs of arthropathy in immature animals of various species ( see ANIMAL PHARMACOLOGY ).

Hypersensitivity Reactions

Serious and occasionally fatal hypersensitivity and/or anaphylactic reactions have been reported in patients receiving therapy with quinolones, including ofloxacin. These reactions often occur following the first dose. Some reactions have been accompanied by cardiovascular collapse, hypotension/shock, seizure, loss of consciousness, tingling, angioedema (including tongue, laryngeal, throat, or facial edema/swelling), airway obstruction (including bronchospasm, shortness of breath, and acute respiratory distress), dyspnea, urticaria, itching, and other serious skin reactions. This drug should be discontinued immediately at the first appearance of a skin rash or any other sign of hypersensitivity. Serious acute hypersensitivity reactions may require treatment with epinephrine and other resuscitative measures, including oxygen, intravenous fluids, antihistamines, corticosteroids, pressor amines, and airway management, as clinically indicated (see PRECAUTIONS and ADVERSE REACTIONS ). Other serious and sometimes fatal events, some due to hypersensitivity, and some due to uncertain etiology, have been reported rarely in patients receiving therapy with quinolones, including ofloxacin. These events may be severe and generally occur following the administration of multiple doses. Clinical manifestations may include one or more of the following: fever, rash, or severe dermatologic reactions (e.g., toxic epidermal necrolysis, Stevens-Johnson syndrome); vasculitis; arthralgia; myalgia; serum sickness; allergic pneumonitis; interstitial nephritis; acute renal insufficiency or failure; hepatitis; jaundice; acute hepatic necrosis or failure; anemia, including hemolytic and aplastic; thrombocytopenia, including thrombotic thrombocytopenic purpura; leukopenia; agranulocytosis; pancytopenia; and/or other hematologic abnormalities. The drug should be discontinued immediately at the first appearance of skin rash, jaundice, or any other sign of hypersensitivity and supportive measures instituted (see PRECAUTIONS, Information for Patients and ADVERSE REACTIONS ). Clostridium difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including ofloxacin tablets, and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile . C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents. If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile, and surgical evaluation should be instituted as clinically indicated (see ADVERSE REACTIONS ). Risk of Aortic Aneurysm and Dissection Fluoroquinolones, including ofloxacin, have been associated with aortic aneurysm and dissection. Findings from epidemiologic studies show a consistently increased risk of hospitalization for aortic aneurysm or dissection within two months following use of a fluoroquinolone antibacterial drug. The annual estimated background risk of aortic aneurysm is as high as approximately 300 aortic aneurysm events per 100,000 persons at the highest risk (e.g., age greater than 85 years). The evidence shows the potential for a 2-fold increased risk over the background risk following fluoroquinolone exposure and was based on a small number of cases, mostly in older patients. The cause for the risk of aortic aneurysm or dissection has not been identified, but the available data suggest that use of fluoroquinolones may contribute in the short term to aneurysm progression. In patients with a known aortic aneurysm or patients who are at greater risk for aortic aneurysms, reserve ofloxacin, for use only when there are no alternative antibacterial treatments available. Ofloxacin has not been shown to be effective in the treatment of syphilis. Fluoroquinolones have been associated with disturbances of blood glucose, including symptomatic hyperglycemia and hypoglycemia, usually in diabetic patients receiving concomitant treatment with an oral hypoglycemic agent (e.g., glyburide) or with insulin. In these patients, careful monitoring of blood glucose is recommended. Severe cases of hypoglycemia resulting in coma or death have been reported. If a hypoglycemic reaction occurs in a patient being treated with ofloxacin, discontinue ofloxacin and initiate appropriate therapy immediately. Antimicrobial agents used in high doses for short periods of time to treat gonorrhea may mask or delay the symptoms of incubating syphilis. All patients with gonorrhea should have a serologic test for syphilis at the time of diagnosis. Patients treated with ofloxacin for gonorrhea should have a follow-up serologic test for syphilis after three months and, if positive, treatment with an appropriate antimicrobial should be instituted.

PRECAUTIONS General Prescribing ofloxacin tablets in the absence of a proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria. Adequate hydration of patients receiving ofloxacin should be maintained to prevent the formation of a highly concentrated urine. Administer ofloxacin with caution in the presence of renal or hepatic insufficiency/impairment. In patients with known or suspected renal or hepatic insufficiency/impairment, careful clinical observation and appropriate laboratory studies should be performed prior to and during therapy since elimination of ofloxacin may be reduced. In patients with impaired renal function (creatinine clearance ≤ 50 mg/mL), alteration of the dosage regimen is necessary (see CLINICAL PHARMACOLOGY and DOSAGE AND ADMINISTRATION ). Moderate to severe photosensitivity/phototoxicity reactions, the latter of which may manifest as exaggerated sunburn reactions (e.g., burning, erythema, exudation, vesicles, blistering, edema) involving areas exposed to light (typically the face, "V" area of the neck, extensor surfaces of the forearms, dorsa of the hands), can be associated with the use of quinolones after sun or UV light exposure. Therefore, excessive exposure to these sources of light should be avoided. Drug therapy should be discontinued if photosensitivity/phototoxicity occurs (See ADVERSE REACTIONS, Postmarketing Adverse Events ). As with other quinolones, ofloxacin should be used with caution in any patient with a known or suspected CNS disorder that may predispose to seizures or lower the seizure threshold (e.g., severe cerebral arteriosclerosis, epilepsy) or in the presence of other risk factors that may predispose to seizures or lower the seizure threshold (e.g., certain drug therapy, renal dysfunction) (see WARNINGS and Drug Interactions ). A possible interaction between oral hypoglycemic drugs (e.g., glyburide/glibenclamide) or with insulin and fluoroquinolone antimicrobial agents have been reported resulting in a potentiation of the hypoglycemic action of these drugs, sometimes resulting in coma or death. The mechanism for this interaction is not known. If a hypoglycemic reaction occurs in a patient being treated with ofloxacin, discontinue ofloxacin immediately and consult a physician (see Drug Interactions and ADVERSE REACTIONS ). As with any potent drug, periodic assessment of organ system functions, including renal, hepatic, and hematopoietic, is advisable during prolonged therapy (see WARNINGS and ADVERSE REACTIONS ). Torsade de Pointes Some quinolones, including ofloxacin, have been associated with prolongation of the QT interval on the electrocardiogram and infrequent cases of arrhythmia. Rare cases of torsade de pointes have been spontaneously reported during postmarketing surveillance in patients receiving quinolones, including ofloxacin. Ofloxacin should be avoided in patients with known prolongation of the QT interval, patients with uncorrected hypokalemia, and patients receiving Class IA (quinidine, procainamide), or Class III (amiodarone, sotalol) antiarrhythmic agents. Information for Patients Advise the patient to read the FDA- approved patient labeling (Medication Guide)

Serious Adverse Reactions

Advise patients to stop taking ofloxacin if they experience an adverse reaction and to call their healthcare provider for advice on completing the full course of treatment with another antibacterial drug. Inform patients of the following serious adverse reactions that have been associated with NOROXIN or other fluoroquinolone use: Disabling and potentially irreversible serious adverse reactions that may occur together: Inform patients that disabling and potentially irreversible serious adverse reactions, including tendinitis and tendon rupture, peripheral neuropathies, and central nervous system effects, have been associated with use of ofloxacin and may occur together in the same patient. Inform patients to stop taking ofloxacin immediately if they experience an adverse reaction and to call their healthcare provider.

Tendon

Disorders: instruct patients to contact their healthcare provider if they experience pain, swelling, or inflammation of a tendon, or weakness or inability to use one of their joints; rest and refrain from exercise; and discontinue ofloxacin treatment. The risk of severe tendon disorders with fluoroquinolones is higher in older patients usually over 60 years of age, in patients taking corticosteroid drugs, and in patients with kidney, heart or lung transplants.

Peripheral

Neuropathies: Inform patients that peripheral neuropathies have been associated with the use of ofloxacin, that symptoms may occur soon after initiation of therapy and may be irreversible. If symptoms of peripheral neuropathy including pain, burning, tingling, numbness, and/or weakness develop, patients should immediately discontinue ofloxacin and contact their physicians. Central nervous system effects (for example, convulsions, dizziness, lightheadedness, increased intracranial pressure) : Inform patients that convulsions have been reported in patients receiving fluoroquinolones, including ofloxacin. Instruct patients to notify their physician before taking this drug if they have a history of convulsions. Inform patients that they should know how they react to ofloxacin before they operate an automobile or machinery or engage in other activities requiring mental alertness and coordination. Instruct patients to notify their physician if persistent headache with or without blurred vision occurs. Myasthenia gravis: inform patients that fluoroquinolones like ofloxacin may cause worsening of myasthenia gravis symptoms, including muscle weakness and breathing problems. Patients should call their healthcare provider right away if you have any worsening muscle weakness or breathing problems.

Hypersensitivity

Reactions: Inform patients that ofloxacin can cause hypersensitivity reactions, even following a single dose, and to discontinue the drug at the first sign of a skin rash, hives or other skin reactions, a rapid heartbeat, difficulty in swallowing or breathing, any swelling suggesting angioedema (for example, swelling of the lips, tongue, face, tightness of the throat, hoarseness), or other symptoms of an allergic reaction. Hepatotoxicity: Inform patients that severe hepatotoxicity (including acute hepatitis and fatal events) has been reported in patients taking ofloxacin. Instruct patients to inform their physician if they experience any signs or symptoms of liver injury including: loss of appetite, nausea, vomiting, fever, weakness, tiredness, right upper quadrant tenderness, itching, yellowing of the skin and eyes, light colored bowel movements or dark colored urine. Diarrhea: Diarrhea is a common problem caused by antibiotics which usually ends when the antibiotic is discontinued. Sometimes after starting treatment with antibiotics, patients can develop watery and bloody stools (with or without stomach cramps and fever) even as late as two or more months after having taken the last dose of the antibiotic. If this occurs, instruct patients to contact their physician as soon as possible. Photosensitivity/Phototoxicity: Inform patients that photosensitivity/phototoxicity has been reported in patients receiving fluoroquinolones. Patients should minimize or avoid exposure to natural or artificial sunlight (tanning beds or UVA/B treatment) while taking quinolones. If patients need to be outdoors while using quinolones, they should wear loose-fitting clothes that protect skin from sun exposure and discuss other sun protection measures with their physician. If a sunburn-like reaction or skin eruption occurs, patients should contact their physician.

Other Information

Patients should be advised: to drink fluids liberally. that mineral supplements, vitamins with iron or minerals, calcium-, aluminum- or magnesium-based antacids, sucralfate or didanosine chewable/buffered tablets or the pediatric powder for oral solution should not be taken within the two-hour period before or within the two-hour period after taking ofloxacin (see Drug Interactions ) that ofloxacin can be taken without regard to meals Patients should be counseled that antibacterial drugs including ofloxacin tablets should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When ofloxacin tablets are prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed. Skipping doses or not completing the full course of therapy may (1) decrease the effectiveness of the immediate treatment and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by ofloxacin tablets or other antibacterial drugs in the future. that if they are diabetic and are being treated with insulin or an oral hypoglycemic drug, to discontinue ofloxacin immediately if a hypoglycemic reaction occurs and consult a physician (see PRECAUTIONS, General and Drug Interactions ); that convulsions have been reported in patients taking quinolones, including ofloxacin, and to notify their physician before taking this drug if there is a history of this condition; to inform their physician of any personal or family history of QTc prolongation or proarrhythmic conditions such as hypokalemia, bradycardia, or recent myocardial ischemia; if they are taking any class IA (quinidine, procainamide), or class III (amiodarone, sotalol) antiarrhythmic agents. Patients should notify their physicians if they have any symptoms of prolongation of the QTc interval including prolonged heart palpitations or a loss of consciousness. Inform patients who have or are at risk for an aortic aneurysm that fluoroquinolones, including ofloxacin, have been associated with a 2-fold increased risk of hospitalization for aortic aneurysm and dissection. Inform patients to seek emergency medical care if they experience sudden chest, stomach, or back pain.

Drug Interactions

Antacids, Sucralfate, Metal Cations, Multivitamins Quinolones form chelates with alkaline earth and transition metal cations. Administration of quinolones with antacids containing calcium, magnesium, or aluminum, with sucralfate, with divalent or trivalent cations such as iron, or with multivitamins containing zinc or with didanosine, chewable/buffered tablets or the pediatric powder for oral solution may substantially interfere with the absorption of quinolones resulting in systemic levels considerably lower than desired. These agents should not be taken within the two-hour period before or within the two-hour period after ofloxacin administration (see DOSAGE AND ADMINISTRATION ).

Caffeine

Interactions between ofloxacin and caffeine have not been detected.

Cimetidine

Cimetidine has demonstrated interference with the elimination of some quinolones. This interference has resulted in significant increases in half-life and AUC of some quinolones. The potential for interaction between ofloxacin and cimetidine has not been studied.

Cyclosporine

Elevated serum levels of cyclosporine have been reported with concomitant use of cyclosporine with some other quinolones. The potential for interaction between ofloxacin and cyclosporine has not been studied.

Drugs

Metabolized by Cytochrome P450 Enzymes Most quinolone antimicrobial drugs inhibit cytochrome P450 enzyme activity. This may result in a prolonged half-life for some drugs that are also metabolized by this system (e.g., cyclosporine, theophylline/methylxanthines, warfarin) when coadministered with quinolones. The extent of this inhibition varies among different quinolones. (see other Drug Interactions ).

Non Steroidal

Anti-Inflammatory Drugs The concomitant administration of a non-steroidal anti-inflammatory drug with a quinolone, including ofloxacin, may increase the risk of CNS stimulation and convulsive seizures (see WARNINGS and PRECAUTIONS, General ).

Probenecid

The concomitant use of probenecid with certain other quinolones has been reported to affect renal tubular secretion. The effect of probenecid on the elimination of ofloxacin has not been studied.

Theophylline

Steady-state theophylline levels may increase when ofloxacin and theophylline are administered concurrently. As with other quinolones, concomitant administration of ofloxacin may prolong the half-life of theophylline, elevate serum theophylline levels, and increase the risk of theophylline-related adverse reactions. Theophylline levels should be closely monitored and theophylline dosage adjustments made, if appropriate, when ofloxacin is coadministered. Adverse reactions (including seizures) may occur with or without an elevation in the serum theophylline level. (see WARNINGS and PRECAUTIONS, General )

Warfarin

Some quinolones have been reported to enhance the effects of the oral anticoagulant warfarin or its derivatives. Therefore, if a quinolone antimicrobial is administered concomitantly with warfarin or its derivatives, the prothrombin time or other suitable coagulation test should be closely monitored.

Antidiabetic

Agents (e.g., Insulin, Glyburide/Glibenclamide) Since disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concurrently with quinolones and an antidiabetic agent, careful monitoring of blood glucose is recommended when these agents are used concomitantly (see PRECAUTIONS, General and Information for Patients ).

Interaction With

Laboratory or Diagnostic Testing Some quinolones, including ofloxacin, may produce false-positive urine screening results for opiates using commercially available immunoassay kits. Confirmation of positive opiate screens by more specific methods may be necessary. Carcinogenesis, Mutagenesis, Impairment of Fertility Long-term studies to determine the carcinogenic potential of ofloxacin have not been conducted. Ofloxacin was not mutagenic in the Ames bacterial test, in vitro and in vivo cytogenetic assay, sister chromatid exchange (Chinese Hamster and Human Cell Lines), unscheduled DNA Repair (UDS) using human fibroblasts, dominant lethal assays, or mouse micronucleus assay. Ofloxacin was positive in the UDS test using rat hepatocytes and Mouse Lymphoma Assay.

Pregnancy Teratogenic Effects Pregnancy

Category C Ofloxacin has not been shown to have any teratogenic effects at oral doses as high as 810 mg/kg/day (11 times the recommended maximum human dose based on mg/m 2 or 50 times based on mg/kg) and 160 mg/kg/day (4 times the recommended maximum human dose based on mg/m 2 or 10 times based on mg/kg) when administered to pregnant rats and rabbits, respectively. Additional studies in rats with oral doses up to 360 mg/kg/day (5 times the recommended maximum human dose based on mg/m 2 or 23 times based on mg/kg) demonstrated no adverse effect on late fetal development, labor, delivery, lactation, neonatal viability, or growth of the newborn. Doses equivalent to 50 and 10 times the recommended maximum human dose of ofloxacin (based on mg/kg) were fetotoxic (i.e., decreased fetal body weight and increased fetal mortality) in rats and rabbits, respectively. Minor skeletal variations were reported in rats receiving doses of 810 mg/kg/day, which is more than 10 times higher than the recommended maximum human dose based on mg/m 2 . There are, however, no adequate and well-controlled studies in pregnant women. Ofloxacin should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus (see WARNINGS ).

Nursing

Mothers In lactating females, a single oral 200 mg dose of ofloxacin resulted in concentrations of ofloxacin in milk that were similar to those found in plasma. Because of the potential for serious adverse reactions from ofloxacin in nursing infants, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother (see WARNINGS and ADVERSE REACTIONS ).

Pediatric Use

Safety and effectiveness in pediatric patients and adolescents below the age of 18 years have not been established. Ofloxacin causes arthropathy (arthrosis) and osteochondrosis in juvenile animals of several species (see WARNINGS ).

Geriatric Use

Geriatric patients are at increased risk for developing severe tendon disorders including tendon rupture when being treated with a fluoroquinolone such as ofloxacin. This risk is further increased in patients receiving concomitant corticosteroid therapy. Tendinitis or tendon rupture can involve the Achilles, hand, shoulder, or other tendon sites and can occur during or after completion of therapy; cases occurring up to several months after fluoroquinolone treatment have been reported. Caution should be used when prescribing ofloxacin to elderly patients especially those on corticosteroids. Patients should be informed of this potential side effect and advised to discontinue ofloxacin and contact their healthcare provider if any symptoms of tendinitis or tendon rupture occur (See Boxed Warning ; WARNINGS ; and ADVERSE REACTIONS, Postmarketing Adverse Event Reports ). In phase 2/3 clinical trials with ofloxacin, 688 patients (14.2%) were ≥ 65 years of age. Of these, 436 patients (9%) were between the ages of 65 and 74 and 252 patients (5.2%) were 75 years or older. There was no apparent difference in the frequency or severity of adverse reactions in elderly adults compared with younger adults. The pharmacokinetic properties of ofloxacin in elderly subjects are similar to those in younger subjects. Drug absorption appears to be unaffected by age. Dosage adjustment is necessary for elderly patients with impaired renal function (creatinine clearance rate ≤ 50 mL/min) due to reduced clearance of ofloxacin. In comparative studies, the frequency and severity of most drug-related nervous system events in patients ≥ 65 years of age were comparable for ofloxacin and control drugs. The only differences identified were an increase in reports of insomnia (3.9% vs. 1.5%) and headache (4.7% vs. 1.8%) with ofloxacin. It is important to note that these geriatric safety data are extracted from 44 comparative studies where the adverse reaction information from 20 different controls (other antibiotics or placebo) were pooled for comparison with ofloxacin. The clinical significance of such a comparison is not clear (see CLINICAL PHARMACOLOGY and DOSAGE AND ADMINISTRATION ). Elderly patients may be more sensitive to drug-associated effects on the QT interval. Therefore, precaution should be taken when using ofloxacin with concomitant drugs that can result in prolongation of the QT interval (e.g. Class IA or Class III antiarrhythmics) or in patients with risk factors for torsade de pointes (e.g. known QT prolongation, uncorrected hypokalemia) (see PRECAUTIONS, General, Torsade de Pointes ). Elderly patients are at greater risk for aortic aneurysm and dissection. A two-fold increased risk of aortic aneurysm and dissection has been reported following use of a fluoroquinolone, including ofloxacin [see Warnings ] .

Drug Interactions Antacids, Sucralfate, Metal Cations, Multivitamins Quinolones form chelates with alkaline earth and transition metal cations. Administration of quinolones with antacids containing calcium, magnesium, or aluminum, with sucralfate, with divalent or trivalent cations such as iron, or with multivitamins containing zinc or with didanosine, chewable/buffered tablets or the pediatric powder for oral solution may substantially interfere with the absorption of quinolones resulting in systemic levels considerably lower than desired. These agents should not be taken within the two-hour period before or within the two-hour period after ofloxacin administration (see DOSAGE AND ADMINISTRATION ).

Caffeine

Interactions between ofloxacin and caffeine have not been detected.

Cimetidine

Cimetidine has demonstrated interference with the elimination of some quinolones. This interference has resulted in significant increases in half-life and AUC of some quinolones. The potential for interaction between ofloxacin and cimetidine has not been studied.

Cyclosporine

Elevated serum levels of cyclosporine have been reported with concomitant use of cyclosporine with some other quinolones. The potential for interaction between ofloxacin and cyclosporine has not been studied.

Drugs

Metabolized by Cytochrome P450 Enzymes Most quinolone antimicrobial drugs inhibit cytochrome P450 enzyme activity. This may result in a prolonged half-life for some drugs that are also metabolized by this system (e.g., cyclosporine, theophylline/methylxanthines, warfarin) when coadministered with quinolones. The extent of this inhibition varies among different quinolones (see other Drug Interactions ).

Non Steroidal

Anti-Inflammatory Drugs The concomitant administration of a non-steroidal anti-inflammatory drug with a quinolone, including ofloxacin, may increase the risk of CNS stimulation and convulsive seizures (see WARNINGS and PRECAUTIONS , General ).

Probenecid

The concomitant use of probenecid with certain other quinolones has been reported to affect renal tubular secretion. The effect of probenecid on the elimination of ofloxacin has not been studied.

Theophylline

Steady-state theophylline levels may increase when ofloxacin and theophylline are administered concurrently. As with other quinolones, concomitant administration of ofloxacin may prolong the half-life of theophylline, elevate serum theophylline levels, and increase the risk of theophylline-related adverse reactions. Theophylline levels should be closely monitored and theophylline dosage adjustments made, if appropriate, when ofloxacin is coadministered. Adverse reactions (including seizures) may occur with or without an elevation in the serum theophylline level (see WARNINGS and PRECAUTIONS , General ).

Warfarin

Some quinolones have been reported to enhance the effects of the oral anticoagulant warfarin or its derivatives. Therefore, if a quinolone antimicrobial is administered concomitantly with warfarin or its derivatives, the prothrombin time or other suitable coagulation test should be closely monitored.

Antidiabetic

Agents (e.g., Insulin, Glyburide/Glibenclamide) Since disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concurrently with quinolones and an antidiabetic agent, careful monitoring of blood glucose is recommended when these agents are used concomitantly (see PRECAUTIONS , General and Information for Patients ).