riMANTAdine

General

Pronunciation:
ri-man-ti-deen

Trade Name(s)

• Flumadine

Ther. Class.

antivirals

Indications

• Prevention and treatment of influenza A infection in high-risk adults.
• Prevention of influenza A infection in high-risk children.

Unlabeled Use(s):

Treatment of influenza A infection in children.

Action

Diminishes replication of influenza A virus by inhibiting uncoating of the virus.

Therapeutic Effect(s):

When given prophylactically, prevents infection with influenza A virus. When administered within 48 hr of onset of infections, decreases the duration of fever and other associated symptoms.

Pharmacokinetics

Absorption: Well absorbed after oral administration.

Distribution: Unknown.

Metabolism and Excretion: Mostly metabolized by the liver; <25% excreted unchanged in urine.

Half-life: 25 hr (range 13–65 hr).

TIME/ACTION PROFILE (plasma concentrations)

Contraindication/Precautions

Contraindicated in:

• Hypersensitivity to rimantadine or amantadine;
• Lactation:  Lactation.

Use Cautiously in:

• History of seizures;
• Severe renal impairment (dose ↓ recommended if CCr <30 mL/min);
• Severe hepatic impairment;
• OB:  Safety not established in pregnancy;
• Geri:  Older adults may be at ↑ risk for GI effects.

Adverse Reactions/Side Effects

Derm: rash

EENT: tinnitus

GI: abdominal pain, anorexia, diarrhea, dry mouth, dyspepsia, nausea, vomiting

Neuro: agitation, depression, dizziness, fatigue, headache, impaired concentration, insomnia, SEIZURES

Resp: dyspnea

* CAPITALS indicate life-threatening.
Underline indicate most frequent.

Interactions

Drug-Drug

•  Aspirin  and  acetaminophen  may ↓ levels and effectiveness.
• May interfere with efficacy of  intranasal influenza virus vaccine ; do not administer within 48 hr before or 2 wk after.

Route/Dosage

PO (Adults): Prevention:  100 mg twice daily (duration range = 11 days-6 wk).  Treatment:  100 mg twice daily for 7 days.

PO Geriatric Patients: Prevention:  100 mg daily.

PO (Children  10–16 yr): Prevention:  100 mg twice daily (duration range = 5–6 wk).

PO (Children  1–9 yr): Prevention:  5 mg/kg/day as a single dose (not to exceed 150 mg/day) (duration range = 5–6 wk).

Renal Impairment 
PO (Adults): Severe renal impairment: Prevention: 100 mg daily.

Hepatic Impairment 
PO (Adults): Severe hepatic impairment: Prevention: 100 mg daily.

Availability (generic available)

Tablets: 100 mg

Assessment

• Monitor respiratory status (rate, breath sounds, sputum) and temperature periodically. Supportive treatment is indicated if symptoms occur.
• Assess for CNS symptoms (dizziness, headache, weakness) and adverse GI effects (nausea/vomiting, abdominal pain).
• Assess and monitor for seizure activity. Immediately discontinue therapy if seizures occur.

Implementation

• Do not administer within 48 hr before or 2 wk after administration of intranasal influenza virus vaccine.

  • Consider available information on influenza drug susceptibility patterns and treatment effects before using rimantadine.
• PO Do not administer last dose of medication near bedtime; may produce insomnia in some patients.

Patient/Family Teaching

• Explain purpose and side effects of medication to patient. Advise patient to read  Patient Information  before starting therapy. Advise patient to take as directed at evenly spaced times for full course of therapy, even if feeling well. Take missed doses as soon as possible unless almost time for next dose; do not double up on missed doses.
• Advise patient to consult health care professional before taking OTC medications or herbal products, especially aspirin or acetaminophen, or drinking alcoholic beverages.
• May cause dizziness. Advise patient to avoid driving or other activities that require alertness until response to the drug is known.
• Advise patient to consult health care professional about receiving a flu vaccination.
• Inform patient that frequent mouth rinses, good oral hygiene, and sugarless gum or candy may ↓ dry mouth.
• Instruct patient and family to notify health care professional if influenza symptoms occur.
• Rep:  Advise women of reproductive potential to notify health care professional if pregnancy is planned or suspected or if breastfeeding.

Evaluation/Desired Outcomes

Prophylactically prevents infection with influenza A virus. When administered within 48 hr of onset of infections, decreases the duration of fever and other associated symptoms.