Influenza Treatment Fact Sheets

Amantadine/Rimantidine Fact Sheet              Printer Friendly Version

Amantadine and Rimantadine are anti-viral medications that prevent Influenza A virus replication.

When do we use Amantadine or Rimantadine?

The drug is used to prevent influenza A or to treat early influenza A. It is used to prevent transmission of influenza A in outbreaks and may be given to persons who cannot receive the vaccine.

How effective are Amantadine and Rimantadine?

Amantadine and Rimantadine are 75-90% effective in preventing influenza A when given prophylactically.  Some studies suggest they are more efficacious when given with the flu vaccine.  Amantadine and rimantadine decrease the severity of influenza A if given within 48 hours of developing symptoms.  They also decrease the duration a person sheds influenza A virus.

What are the side effects of Amantadine and Rimantadine?

Amantadine and Rimantadine can cause gastorintestinal and central nervous system side effects including nausea, vomiting, diarrhea, irritability, difficulty sleeping or concentrating.  If these side effects occur the dose is reduced by half (100mg daily). Persons taking Amantadine or Rimantadine should not use alcohol because alcohol can worsen the central nervous system side effects of the drug.

What is the dose of Amantadine or Rimantadine?

The usual dose is 100 mg by mouth twice a day.   The dose is reduced for renal failure and in the elderly.

Who cannot take Amantadine or Rimantadine?

There are limited data about the use of amantadine and rimantadine durting pregnancy.

 

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Oseltamivir is an anti-viral medication that prevents Influenza A and B virus replication.

When do we use Oseltamivir?

The drug is used to prevent and or treat early influenza.  It is used to prevent transmission of influenza in outbreaks and may be given to persons who cannot receive the vaccine.

How effective is Oseltamivir?

Oseltamivir is 92% effective in preventing illness and 76-92% effective in preventing febrile influenza when given prophylactically. If used for treatment, it should be given within 48 hours of symptom onset.  Oseltamivir can be given with the flu vaccine.  Oseltamivir decreases the severity, the incidence of complications and duration of influenza (by 1 day) if given within 48 hours of developing symptoms.  It also decreases the duration a person sheds influenza virus.

What are the side effects of Oseltamivir?

Side effects are rare and include nausea and vomitting.

What is the dose of Oseltamivir?

When used for treatment, the dose is 75 mg by mouth twice a day.

Who cannot take Oseltamivir?

There is limited data about the use of neuraminidase inhibitors during pregnancy.

 

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