Rimantadine Hydrochloride Tablets USP
100 mg
Rx only

DESCRIPTION: Rimantadine hydrochloride is a synthetic antiviral drug available as a 100 mg film-coated tablet for oral administration. Each rimantadine hydrochloride tablet USP contains 100 mg of rimantadine hydrochloride USP. In addition, it also contains the following inactive ingredients:
corn starch, FD&C Yellow No. 6 Lake, hypromellose, magnesium stearate, microcrystalline cellulose, polyethylene glycol, propylene glycol and sodium starch glycolate.

Rimantadine hydrochloride is a white to off-white crystalline powder which is freely soluble in water (50 mg/mL at 20°C). Chemically, rimantadine hydrochloride is alpha-methyltricyclo-(3.3.1.1/3.7)decane-1-methanamine hydrochloride, with an empirical formula of C₁₂H₂₁N•HCl, a molecular weight of 215.77 and the following structural formula:

CONTRAINDICATIONS: Rimantadine hydrochloride is contraindicated in patients with known hypersensitivity to drugs of the adamantane class, including rimantadine and amantadine.

ADVERSE REACTIONS: In 1,027 patients treated with rimantadine hydrochloride in controlled clinical trials at the recommended dose of 200 mg daily, the most frequently reported adverse events involved the gastrointestinal and nervous systems.

Incidence >1%: Adverse events reported most frequently (1 to 3%) at the recommended dose in controlled clinical trials are shown in the table below.

	Rimantadine (n=1027)	Control (n=986)
Nervous System
Insomnia	2.1%	0.9%
Dizziness	1.9%	1.1%
Headache	1.4%	1.3%
Nervousness	1.3%	0.6%
Fatigue	1.0%	0.9%
Gastrointestinal System
Nausea	2.8%	1.6%
Vomiting	1.7%	0.6%
Anorexia	1.6%	0.8%
Dry Mouth	1.5%	0.6%
Abdominal pain	1.4%	0.8%
Body as a Whole
Asthenia	1.4%	0.5%

Less frequent adverse events (0.3 to 1%) at the recommended dose in controlled clinical trials were: Gastrointestinal System: diarrhea, dyspepsia; Nervous System: impairment of concentration, ataxia, somnolence, agitation, depression; Skin and Appendages: rash; Hearing and Vestibular: tinnitus; Respiratory: dyspnea.

Additional adverse events (less than 0.3%) reported at recommended doses in controlled clinical trials were: Nervous System: gait abnormality, euphoria, hyperkinesia, tremor, hallucination, confusion, convulsions; Respiratory: bronchospasm, cough; Cardiovascular: pallor, palpitation, hypertension, cerebrovascular disorder, cardiac failure, pedal edema, heart block, tachycardia, syncope; Reproduction: non-puerperal lactation; Special Senses: taste loss/change, parosmia.

Rates of adverse events, particularly those involving the gastrointestinal and nervous systems, increased significantly in controlled studies using higher than recommended doses of rimantadine hydrochloride. In most cases, symptoms resolved rapidly with discontinuation of treatment. In addition to the adverse events reported above, the following were also reported at higher than recommended doses: increased lacrimation, increased micturition frequency, fever, rigors, agitation, constipation, diaphoresis, dysphagia, stomatitis, hypesthesia and eye pain.

Adverse Reactions in Trials of Rimantadine and Amantadine: In a six-week prophylaxis study of 436 healthy adults comparing rimantadine with amantadine and placebo, the following adverse reactions were reported with an incidence >1%.

	Rimantadine 200 mg/day (n=145)	Placebo (n=143)	Amantadine 200 mg/day (n=148)
Nervous System
Insomnia	3.4%	0.7%	7.0%
Nervousness	2.1%	0.7%	2.8%
Impaired Concentration	2.1%	1.4%	2.1%
Dizziness	0.7%	0.0%	2.1%
Depression	0.7%	0.7%	3.5%
Total % of subjects with adverse reactions	6.9%	4.1%	14.7%
Total % of subjects withdrawn due to adverse reactions	6.9%	3.4%	14.0%

OVERDOSAGE: As with any overdose, supportive therapy should be administered as indicated. Overdoses of a related drug, amantadine, have been reported with adverse reactions consisting of agitation, hallucinations, cardiac arrhythmia and death. The administration of intravenous physostigmine (a cholinergic agent) at doses of 1 to 2 mg in adults (Ref. 7) and 0.5 mg in children (Ref. 8) repeated as needed as long as the dose did not exceed 2 mg/hour has been reported anecdotally to be beneficial in patients with central nervous system effects from overdoses of amantadine.

HOW SUPPLIED: Rimantadine hydrochloride tablets USP 100 mg are supplied as orange, round film coated tablets in bottles of 100 (NDC 0781-5029-01) and 1000 (NDC 0781-5029-10). Debossed “cor” on one side and “111” on other side.

Store at controlled room temperature 15° - 30°C (59° - 86°F). (see USP).

Dispense in a tight container as defined in the USP.

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