What is Arcamin prescribed for?

Arcamin (Rimantadine) Usage in Clinical Practice

Rimantadine (Arcamin) is primarily prescribed for the prevention and treatment of influenza A viral infections, particularly in institutional outbreaks and for individuals at high risk of complications. 1

Primary Indications

Rimantadine is indicated for:

• Prophylaxis against influenza A infections in adults and children ≥1 year old 1
• Treatment of influenza A infections in adults (though some specialists consider it appropriate for treatment in children as well) 1

Dosage Recommendations

For Adults:

• Standard dose: 100 mg twice daily (200 mg/day) 1
• Adults ≥65 years: 100 mg/day for prophylaxis and treatment due to increased risk of side effects 1
• Nursing home residents: 100 mg/day for treatment 1

For Children:

• Ages 1-9 years: 5 mg/kg/day in 1-2 divided doses, not exceeding 150 mg/day 1
• Ages ≥10 years: 200 mg/day (100 mg twice daily), but for children <40 kg, 5 mg/kg/day is recommended regardless of age 1

For Patients with Renal Impairment:

• Creatinine clearance <10 mL/min: Reduce to 100 mg/day 1
• Patients with any degree of renal insufficiency should be monitored for adverse effects 1

Clinical Applications

Rimantadine is particularly useful in:

1. Institutional outbreak control (nursing homes, dormitories, cruise ships) 1
2. Post-exposure prophylaxis for unvaccinated high-risk individuals 1
3. Supplemental protection when the circulating influenza strain is not well-matched by the vaccine 1

Side Effects and Precautions

• Common side effects: CNS symptoms (less severe than amantadine), gastrointestinal symptoms 1
• Elderly patients: Lower incidence of CNS side effects compared to amantadine, but higher serum concentrations observed in chronically ill older persons 1
• Monitoring: Patients with renal insufficiency require careful observation for adverse reactions 1

Clinical Considerations

• To limit potential transmission of drug-resistant virus during outbreaks, separate patients receiving treatment from those on prophylaxis 1
• Rimantadine is only effective against influenza A viruses, not influenza B 1
• When used for prophylaxis during institutional outbreaks, continue until approximately 1 week after the end of the outbreak 1

Important Distinctions from Other Antivirals

Unlike newer neuraminidase inhibitors (zanamivir, oseltamivir), rimantadine:

• Works through a different mechanism (M2 ion channel inhibition)
• Has a different side effect profile
• Is typically less expensive
• Has more established resistance patterns

Rimantadine shows lower CNS side effect incidence compared to amantadine, making it preferable in elderly patients who need an adamantane antiviral 1.