OSELTAMIVIR Drug Interactions: What You Need to Know

INTERACTIONS Live attenuated influenza vaccine (LAIV), intranasal: Avoid administration of LAIV within 2 weeks before or 48 hours after oseltamivir phosphate for oral suspension use, unless medically indicated. ( 7 )

7.1 Influenza Vaccines Live Attenuated Influenza Vaccine The concurrent use of oseltamivir phosphate with live attenuated influenza vaccine (LAIV) intranasal has not been evaluated. However, because of the potential for oseltamivir phosphate to inhibit replication of live vaccine virus and possibly reduce the efficacy of LAIV, avoid administration of LAIV within 2 weeks before or 48 hours after oseltamivir phosphate administration, unless medically indicated.

Inactivated Influenza Vaccine

Inactivated influenza vaccine can be administered at any time relative to use of oseltamivir phosphate.

7.2 Drugs Without Clinically Significant Drug Interaction with Oseltamivir Phosphate for Oral Suspension No dose adjustments are needed for either oseltamivir or the concomitant drug when coadministering oseltamivir with amoxicillin, acetaminophen, aspirin, cimetidine, antacids (magnesium and aluminum hydroxides and calcium carbonates), rimantadine, amantadine, or warfarin <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span> .

7.1 Influenza Vaccines Live Attenuated Influenza Vaccine The concurrent use of oseltamivir phosphate with live attenuated influenza vaccine (LAIV) intranasal has not been evaluated. However, because of the potential for oseltamivir phosphate to inhibit replication of live vaccine virus and possibly reduce the efficacy of LAIV, avoid administration of LAIV within 2 weeks before or 48 hours after oseltamivir phosphate administration, unless medically indicated.

Inactivated Influenza Vaccine

Inactivated influenza vaccine can be administered at any time relative to use of oseltamivir phosphate.

7.2 Drugs Without Clinically Significant Drug Interaction with Oseltamivir Phosphate for Oral Suspension No dose adjustments are needed for either oseltamivir or the concomitant drug when coadministering oseltamivir with amoxicillin, acetaminophen, aspirin, cimetidine, antacids (magnesium and aluminum hydroxides and calcium carbonates), rimantadine, amantadine, or warfarin <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span> .

Oseltamivir phosphate for oral suspension is contraindicated in patients with known serious hypersensitivity to oseltamivir or any component of the product. Severe allergic reactions have included anaphylaxis and serious skin reactions including toxic epidermal necrolysis, Stevens- Johnson Syndrome, and erythema multiformec [see Warnings and Precautions ( 5.1 )] . Patients with known serious hypersensitivity to oseltamivir or any of the components of oseltamivir phosphate for oral suspension ( 4 )

AND PRECAUTIONS Serious skin/hypersensitivity reactions such as Stevens-Johnson Syndrome, toxic epidermal necrolysis and erythema multiforme: Discontinue Oseltamivir Phosphate for Oral Suspension and initiate appropriate treatment if allergic-like reactions occur or are suspected. ( 5.1 ) Neuropsychiatric events: Patients with influenza, including those receiving Oseltamivir Phosphate for Oral Suspension , particularly pediatric patients, may be at an increased risk of confusion or abnormal behavior early in their illness. Monitor for signs of abnormal behavior. ( 5.2 )

5.1 Serious Skin/Hypersensitivity Reactions Cases of anaphylaxis and serious skin reactions including toxic epidermal necrolysis, Stevens-Johnson Syndrome, and erythema multiforme have been reported in postmarketing experience with Oseltamivir Phosphate for Oral Suspension.

Stop Oseltamivir

Phosphate for Oral Suspension and institute appropriate treatment if an allergic-like reaction occurs or is suspected. The use of Oseltamivir Phosphate for Oral Suspension is contraindicated in patients with known serious hypersensitivity to Oseltamivir Phosphate for Oral Suspension [see Contraindications ( 4 ) and Adverse Reactions ( 6.2 )] .

5.2 Neuropsychiatric Events There have been postmarketing reports of delirium and abnormal behavior leading to injury, and in some cases resulting in fatal outcomes, in patients with influenza who were receiving Oseltamivir Phosphate for Oral Suspension <span class="opacity-50 text-xs">[see Adverse Reactions ( 6.2 )]</span> . Because these events were reported voluntarily during clinical practice, estimates of frequency cannot be made but they appear to be uncommon based on Oseltamivir Phosphate for Oral Suspension usage data. These events were reported primarily among pediatric patients and often had an abrupt onset and rapid resolution. The contribution of Oseltamivir Phosphate for Oral Suspension to these events has not been established. Influenza can be associated with a variety of neurologic and behavioral symptoms that can include events such as hallucinations, delirium, and abnormal behavior, in some cases resulting in fatal outcomes. These events may occur in the setting of encephalitis or encephalopathy but can occur without obvious severe disease. Closely monitor oseltamivir phosphate for oral suspension-treated patients with influenza for signs of abnormal behavior. If neuropsychiatric symptoms occur, evaluate the risks and benefits of continuing Oseltamivir Phosphate for Oral Suspension for each patient.

5.3 Risk of Bacterial Infections There is no evidence for efficacy of Oseltamivir Phosphate for Oral Suspension in any illness caused by pathogens other than influenza viruses. Serious bacterial infections may begin with influenza-like symptoms or may coexist with or occur as complications during the course of influenza.

Oseltamivir

Phosphate for Oral Suspension has not been shown to prevent such complications. Prescribers should be alert to the potential for secondary bacterial infections and treat them as appropriate.

5.4 Fructose Intolerance in Patients with Hereditary Fructose Intolerance Fructose can be harmful to patients with hereditary fructose intolerance. One dose of 75 mg Oseltamivir Phosphate for Oral Suspension delivers 2 grams of sorbitol. This is above the daily maximum limit of sorbitol for patients with hereditary fructose intolerance and may cause dyspepsia and diarrhea.

5.1 Serious Skin/Hypersensitivity Reactions Cases of anaphylaxis and serious skin reactions including toxic epidermal necrolysis, Stevens-Johnson Syndrome, and erythema multiforme have been reported in postmarketing experience with Oseltamivir Phosphate for Oral Suspension.

Stop Oseltamivir

Phosphate for Oral Suspension and institute appropriate treatment if an allergic-like reaction occurs or is suspected. The use of Oseltamivir Phosphate for Oral Suspension is contraindicated in patients with known serious hypersensitivity to Oseltamivir Phosphate for Oral Suspension [see Contraindications ( 4 ) and Adverse Reactions ( 6.2 )] .

5.2 Neuropsychiatric Events There have been postmarketing reports of delirium and abnormal behavior leading to injury, and in some cases resulting in fatal outcomes, in patients with influenza who were receiving Oseltamivir Phosphate for Oral Suspension <span class="opacity-50 text-xs">[see Adverse Reactions ( 6.2 )]</span> . Because these events were reported voluntarily during clinical practice, estimates of frequency cannot be made but they appear to be uncommon based on Oseltamivir Phosphate for Oral Suspension usage data. These events were reported primarily among pediatric patients and often had an abrupt onset and rapid resolution. The contribution of Oseltamivir Phosphate for Oral Suspension to these events has not been established. Influenza can be associated with a variety of neurologic and behavioral symptoms that can include events such as hallucinations, delirium, and abnormal behavior, in some cases resulting in fatal outcomes. These events may occur in the setting of encephalitis or encephalopathy but can occur without obvious severe disease. Closely monitor oseltamivir phosphate for oral suspension-treated patients with influenza for signs of abnormal behavior. If neuropsychiatric symptoms occur, evaluate the risks and benefits of continuing Oseltamivir Phosphate for Oral Suspension for each patient.

5.3 Risk of Bacterial Infections There is no evidence for efficacy of Oseltamivir Phosphate for Oral Suspension in any illness caused by pathogens other than influenza viruses. Serious bacterial infections may begin with influenza-like symptoms or may coexist with or occur as complications during the course of influenza.

Oseltamivir

Phosphate for Oral Suspension has not been shown to prevent such complications. Prescribers should be alert to the potential for secondary bacterial infections and treat them as appropriate.

5.4 Fructose Intolerance in Patients with Hereditary Fructose Intolerance Fructose can be harmful to patients with hereditary fructose intolerance. One dose of 75 mg Oseltamivir Phosphate for Oral Suspension delivers 2 grams of sorbitol. This is above the daily maximum limit of sorbitol for patients with hereditary fructose intolerance and may cause dyspepsia and diarrhea.