BETHANECHOL: 150 Adverse Event Reports & Safety Profile

DESCRIPTION Bethanechol chloride, a cholinergic agent, is a synthetic ester which is structurally and pharmacologically related to acetylcholine. It is designated chemically as 2-[(aminocarbonyl) oxy]- N,N,N -trimethyl-1-propanaminium chloride. Its molecular formula is C 7 H 17 CIN 2 O 2 and its structural formula is: Bethanechol chloride, USP is a white, hygroscopic crystalline powder having a slight amine-like odor, freely soluble in water, and has a molecular weight of 196.68. Each tablet for oral administration contains 5 mg, 10 mg, 25 mg or 50 mg bethanechol chloride, USP. Bethanechol chloride Tablets, USP also contain the following inactive ingredients: anhydrous lactose, colloidal silicon dioxide, magnesium stearate, microcrystalline cellulose and sodium starch glycolate, Type A.

The

25 mg and 50 mg tablets also contain D&C Yellow No.10 Aluminum Lake and FD&C Yellow No. 6 Aluminum Lake.

Structural

Formula

INDICATIONS AND USAGE Bethanechol Chloride Tablets, USP are indicated for the treatment of acute postoperative and postpartum nonobstructive (functional) urinary retention and for neurogenic atony of the urinary bladder with retention.

DOSAGE AND ADMINISTRATION Dosage must be individualized, depending on the type and severity of the condition to be treated. Preferably give the drug when the stomach is empty. If taken soon after eating, nausea and vomiting may occur. The usual adult oral dose ranges from 10 mg to 50 mg three or four times a day. The minimum effective dose is determined by giving 5 mg to 10 mg initially, and repeating the same amount at hourly intervals until satisfactory response occurs, or until a maximum of 50 mg has been given. The effects of the drug sometimes appear within 30 minutes, and are usually maximal within 60 to 90 minutes. The drug effects persist for about one hour. If necessary, the effects of the drug can be abolished promptly by atropine (see OVERDOSAGE ).

CONTRAINDICATIONS Hypersensitivity to bethanechol chloride tablets, hyperthyroidism, peptic ulcer, latent or active bronchial asthma, pronounced bradycardia or hypotension, vasomotor instability, coronary artery disease, epilepsy and parkinsonism. Bethanechol chloride should not be employed when the strength or integrity of the gastrointestinal or bladder wall is in question, or in the presence of mechanical obstruction; when increased muscular activity of the gastrointestinal tract or urinary bladder might prove harmful, as following recent urinary bladder surgery, gastrointestinal resection and anastomosis, or when there is possible gastrointestinal obstruction; in bladder neck obstruction, spastic gastrointestinal disturbances, acute inflammatory lesions of the gastrointestinal tract, or peritonitis; or in marked vagotonia.

ADVERSE REACTIONS Adverse reactions are rare following oral administration of bethanechol chloride, but are more common following subcutaneous injection. Adverse reactions are more likely to occur when dosage is increased. The following adverse reactions have been observed: Body as a Whole: malaise Digestive: abdominal cramps or discomfort, colicky pain, nausea and belching, diarrhea, borborygmi, salivation Renal: urinary urgency Nervous System: headache Cardiovascular: a fall in blood pressure with reflex tachycardia, vasomotor response Skin: flushing producing a feeling of warmth, sensation of heat about the face, sweating Respiratory: bronchial constriction, asthmatic attacks Special Senses : lacrimation, miosis Causal Relationship Unknown: The following adverse reactions have been reported, and a causal relationship to therapy with bethanechol chloride has not been established: Body as a Whole: malaise Nervous System: seizures To report SUSPECTED ADVERSE REACTIONS, contact Amneal Pharmaceuticals at 1-877-835-5472 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .

PRECAUTIONS General In urinary retention, if the sphincter fails to relax as bethanechol chloride contracts the bladder, urine may be forced up the ureter into the kidney pelvis. If there is bacteriuria, this may cause reflux infection. Information for Patients Bethanechol chloride tablets should preferably be taken one hour before or two hours after meals to avoid nausea or vomiting. Dizziness, lightheadedness or fainting may occur, especially when getting up from a lying or sitting position.

Drug Interactions

Special care is required if this drug is given to patients receiving ganglion blocking compounds because a critical fall in blood pressure may occur. Usually, severe abdominal symptoms appear before there is such a fall in the blood pressure. Carcinogenesis, Mutagenesis, Impairment of Fertility Long-term studies in animals have not been performed to evaluate the effects upon fertility, mutagenic or carcinogenic potential of bethanechol chloride.

Pregnancy Teratogenic Effects Pregnancy

Category C Animal reproduction studies have not been conducted with bethanechol chloride. It is also not known whether bethanechol chloride can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Bethanechol chloride should be given to a pregnant woman only if clearly needed.

Nursing

Mothers It is not known whether this drug is secreted in human milk. Because many drugs are secreted in human milk and because of the potential for serious adverse reactions from bethanechol chloride 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.

Pediatric Use

Safety and effectiveness in pediatric patients have not been established.

Drug Interactions Special care is required if this drug is given to patients receiving ganglion blocking compounds because a critical fall in blood pressure may occur. Usually, severe abdominal symptoms appear before there is such a fall in the blood pressure.