No

Antiviral Agent

Prophylaxis (adults and children >1 year) and treatment (adults) of influenza A viral infection

C

Clinical effects on the fetus: Embryotoxic in high dose rat studies

Breast-feeding/lactation: Avoid use in nursing mothers due to potential adverse effect in infants; rimantadine is concentrated in milk

Hypersensitivity to drugs of the adamantine class, including rimantadine and amantadine

Use with caution in patients with renal and hepatic dysfunction; avoid use, if possible, in patients with recurrent and eczematoid dermatitis, uncontrolled psychosis, or severe psychoneurosis. An increase in seizure incidence may occur in patients with seizure disorders; discontinue drug if seizures occur; consider the development of resistance during rimantadine treatment of the index case as likely if failure of rimantadine prophylaxis among family contact occurs and if index case is a child; viruses exhibit cross-resistance between amantadine and rimantadine.

1% to 10%:

Central nervous system: Dizziness (1.9%), confusion, headache (1.4%), insomnia (2.1%), difficulty in concentrating, anxiety (1.3%), restlessness, irritability, hallucinations; incidence of CNS side effects may be less than that associated with amantadine

Gastrointestinal: Nausea (2.8%), vomiting (1.7%), xerostomia (1.5%), abdominal pain (1.4%), anorexia (1.6%)

Genitourinary: Urinary retention

Agitation, hallucinations, ventricular cardiac arrhythmias (torsade de pointes and PVCs), slurred speech, anticholinergic effects (dry mouth, urinary retention and mydriasis), ataxia, tremor, myoclonus, seizures and death have been reported with amantadine, a related drug

Treatment is symptomatic (do not use physostigmine); tachyarrhythmias may be treated with beta-blockers such as propranolol; dialysis is not recommended except possibly in renal failure

Acetaminophen: Reduction in AUC and peak concentration of rimantadine

Aspirin: Peak plasma and AUC concentrations of rimantadine are reduced

Cimetidine: Rimantadine clearance is decreased (~16%)

Exerts its inhibitory effect on three antigenic subtypes of influenza A virus (H1N1, H2N2, H3N2) early in the viral replicative cycle, possibly inhibiting the uncoating process; it has no activity against influenza B virus and is two- to eightfold more active than amantadine

Absorption: Tablet and syrup formulations are equally absorbed; T_max: 6 hours

Metabolism: Extensive in the liver

Half-life: 25.4 hours (increased in elderly)

Elimination: <25% of dose excreted in urine as unchanged drug; hemodialysis does not contribute to the clearance of rimantadine; no data exist establishing a correlation between plasma concentration and antiviral effect

Oral:

Children <10 years: 5 mg/kg once daily; maximum: 150 mg

Children >10 years and Adults: 100 mg twice daily; decrease to 100 mg/day in elderly or in patients with severe hepatic or renal impairment (Cl_cr less than or equal to 10 mL/minute)

Treatment: Adults: 100 mg twice daily; decrease to 100 mg/day in elderly or in patients with severe hepatic or renal impairment (Cl_cr less than or equal to 10 mL/minute)

Food does not affect rate or extent of absorption

Monitor for CNS or GI effects in elderly or patients with renal or hepatic impairment

May cause dizziness, anxiety, confusion, insomnia, restlessness, irritability, or hallucinations

None reported

No information available to require special precautions

No effects or complications reported

Take as directed, for full course of therapy. Use caution when changing position (rising from sitting or lying) until response is known. Report CNS changes (eg, confusion, insomnia, anxiety, restlessness, irritability, hallucinations), difficulty urinating, or severe nausea or vomiting. Pregnancy/breast-feeding precautions: Inform prescriber if you are or intend to be pregnant. Do not breast-feed.

Avoid use in pregnant or breast-feeding women

Syrup, as hydrochloride: 50 mg/5 mL (60 mL, 240 mL, 480 mL)

Tablet, as hydrochloride: 100 mg

Bentley DW, Karki SD, and Betts RF, "Rimantadine and Seizures," Ann Intern Med, 1989, 110(4):323-4.

Dolin R, Reichman RC, Madore HP, et al, "A Controlled Trial of Amantadine and Rimantadine in the Prophylaxis of Influenza A Infection," N Engl J Med, 1982, 307(10):580-4.

Douglas RG Jr, "Prophylaxis and Treatment of Influenza," N Engl J Med, 1990, 322(7):443-50.

"Drugs for Non-HIV Viral Infections," Med Lett Drugs Ther, 1994, 36(919):27.

Guay DR, "Amantadine and Rimantadine Prophylaxis of Influenza A in Nursing Homes," Drugs Aging, 1994, 5(1):8-19.

Keating MR, "Antiviral Agents," Mayo Clin Proc, 1992, 67(2):160-78.

Patriarca PA, Kater NA, Kendal AP, et al, "Safety of Prolonged Administration of Rimantadine Hydrochloride in the Prophylaxis of Influenza A Virus Infections in Nursing Homes," Antimicrob Agents Chemother, 1984, 26(1):101-3.

Wintermeyer SM and Nahata MC, "Rimantadine: A Clinical Perspective," Ann Pharmacother, 1995, 29(3):299-310.