Drug Interaction:
Interacting drugs- summary
+ Rimantadine-
Acetaminophen +
Coadmin with acetoaminophen reduced the peak concentration
and AUC values for rimantadine
Aspirin +
Peak plasma and AUC of rimantadine reduced
Cimetidine +
When a single dose of 100mg of rimantadine was administered
1 hour after cimetidine(300mg 4 times a day) in healthy adults,
the apparent total rimantadine clearance was reduced by 16%
Indication:
Prophylaxis against influenza virus
Adverse Reaction:
Most frequently reported adverse events invloved GI and CNS
CNS-
Insomnia 2% dizziness 2% headache 1% nervousness 1% fatigue 1% asthenia 1.4%
GI-
Nausea 3% vomiting 2% anorexia 2% dry mouth 2% abdominal pain 1%
Contra-Indications:
Hypersens to drugs of the adamantine class, incuding rimantadine and amantadine
Special precautions:
Seizures- increased in patients with history of epilepsy.
Resistence - emergence of resistence strains of influenza virus during treatment
Seizures- an increased incidence of seizures has been reported in patients with a history of epilepy who received the related drug amantadine. If seizures develop discontinue the drug.
Resistence- consider transmission of rimantadine- resistent virus when treating patients whose contacts are at high risk for infuenza A illness.
Influenza A virus strains resistent to rimantidine can emerge during treatment and may be transmissible and cause typical influenza illness.
Warnings-
Renal/hepatic function impairment- the safety and pharmacokinetics of rimantidine in renal and hepatic insufficiency have not been evaluated after single dose administration.
Because of the potential accumulation of rimantidine and its metabolites in polasma, excercise caution when patients with renal or hepatic insufficiency are treated with rimantadine.
Pregnancy- Use during pregnancy only if the potential benefits justifies the risk to the fetus.
Lacatation- Rimatadine should not be administered to nursing mothers because of the adverse effects noted in the offsping of rats treated with rimantidine during the nursing period.
Children- safety and efficacy of rimantadine in the treatment of symptomatic influenza infection in children have not been established.
Dosages/ Overdosage Etc:
Approved by FDA on September 17,1993
Indications:
Prophylaxis against influenza virus
Dosage:
Adults- recommended dose- 100mg twice daily
Children below 10 years- administer once a day at a dose of 5mg/kg not exceeding 150mg.
Patient Information:
Ref - USP PDI Vol II 17th Edition (1997)
RIMANTIDINE - SYSTEMIC
1.Allergies-
Tell your doctor if you have ever had any unusual or allergic reaction to
Rimantidine or amantidine. Also tell your healthcare care professional
if you are allergic to any other substances such as foods. preservatives or dyes.
2.Pregnancy-
Studies have not been done in humans. However, studies in some animals,
have shown that rimantidine is harmful to the fetus and causes birth defects.
3. Breast-feeding-
It is not known whether if ramantidine passes into breast milk. Although most
medicines pass into breast milk in small amounts,many of them may be used
safely while breast-feeding. Mothers who are taking this medicine and who wish
to breast feed should discuss this with their doctor.
4.Children-
This medicine has been tested in children over 1 year of age, and has
not shown to cause different side effects or problems in these children than
it does in adults. There is no specific information on the use of rimantidine
in children under 1 year of age with use in other age groups.
5.Older adults-
Difficuly in sleeping, difficulty in concentrating , dizziness, headache,
nervousness and pain may be especially likely to occur . Stomach pain
nausea, vomitiing, and loss of appetite may also occur.
6. Other medicines-
Tell your doctor if you are using any or /other prescription or
non-prescription (Over-the counter) OTC medicine.
7. Other medical problems-
Make sure you tell your doctor if you have any other medical problems
especially-
Epilepsy or other seizures - ramantidine may increase the frequency of
convulsuions in patients with a seizure disorder
Kidney disease- rimantidine is removed from the body by the kidneys,
patients with severe kidney disease will need to receive a lower dose
of rimantidine
Liver disease- patients with liver disease may need to receive a lower
dose of rimantidine
Pharmacology/ Pharmacokinetics:
Pharmacology:
Rimantadine is a synthetic antiviral agent. The mechanism of action is not understood.It appears to exert its inhibitory effect early in viral replicative cycle, possibly inhibiting the uncoating of the virus.
Pharmacokinetics-
There are no data establishing a correlation between plasma concentration and antiviral effect.
Pregnancy and lactation:
Pregnancy:
Use only if the potential benefits outweighs the potential risks to the fetus. Lactation: Rimantadine should not be administered to nursing mothers.
Children-
Safety and efficacy of rimantadine in the treatment of symptomatic inflenza infection in children have not been established.
Manufacturer Details