Description and Brand Names

Drug information provided by: Merative, Micromedex®

US Brand Name

  1. Flumadine

Descriptions


Rimantadine is used to prevent or treat certain influenza (flu) infections (type A) in adults (17 years of age and older). It is also used to prevent flu infection (type A) in children (1 to 16 years of age). It may be given alone or along with flu shots.

Rimantadine is an antiviral. It will not work for colds, other types of flu, or other virus infections.

This medicine is available only with your doctor's prescription.

This product is available in the following dosage forms:

  • Tablet

Before Using

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of rimantadine in children. However, safety and efficacy have not been established in children younger than 1 year of age.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of rimantadine in the elderly. However, elderly patients are more likely to have unwanted side effects (e.g., anxiety, dizziness, nausea, vomiting, stomach pain), which may require caution and an adjustment in the dose for patients receiving rimantadine.

Breastfeeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Drug Interactions

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.

Other Interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Epilepsy or seizures, history of—Use with caution. May make these conditions worse.
  • Kidney disease, severe or
  • Liver disease, severe—Use with caution. The effects of this medicine may be increased because of slower removal from the body.

Proper Use

Talk to your doctor about the possibility of getting a flu shot if you have not had one yet.

This medicine is best taken before exposure, or as soon as possible after exposure, to people who have the flu.

To help keep yourself from getting the flu, keep taking this medicine for the full time of treatment.

If you already have the flu, continue taking this medicine for the full time of treatment even if you begin to feel better after a few days. This will help to clear up your infection completely. If you stop taking this medicine too soon, your symptoms may return. This medicine should be taken for at least 5 to 7 days.

This medicine works best when there is a constant amount in the blood. To help keep the amount constant, do not miss any doses. Also, it is best to take the doses at evenly spaced times day and night.

Shake the oral liquid well before each use. Measure the medicine with a specially marked measuring spoon or other device to measure each dose accurately. The average household teaspoon may not hold the right amount of liquid.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage forms (suspension or tablets):
    • For treatment of flu:
      • Adults and teenagers 17 years of age and older—100 milligrams (mg) two times a day for 7 days.
      • Older adults—100 mg once a day.
      • Children up to 16 years of age—Use is not recommended.
    • For prevention of flu:
      • Adults and teenagers 17 years of age and older—100 milligrams (mg) two times a day.
      • Older adults—100 mg once a day.
      • Children 10 to 16 years of age—100 mg two times a day.
      • Children 1 to 9 years of age—Dose is based on body weight and must be determined by your doctor. The dose is 5 milligrams (mg) per kilogram (kg) of body weight once a day. Children in this age group should not receive more than 150 mg per day.
      • Children younger than 1 year of age—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Store the oral liquid at room temperature for 14 days.

Precautions

It is important that your doctor check the progress of you or your child at regular visits to allow changes in your dose and to check for any unwanted effects.

This medicine may cause some people to become dizzy or confused, or to have trouble concentrating. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy or confused. If these reactions are especially bothersome, check with your doctor.

If your or your child's symptoms do not improve within a few days, or if they become worse, check with your doctor.

While you are being treated with rimantadine, do not have any immunizations (vaccinations) without your doctor's approval. Live virus vaccinations should not be given for 2 days after stopping rimantadine, and this medicine should be not be given 2 weeks after receiving live vaccines.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Less common

  1. Difficult or labored breathing
  2. shortness of breath
  3. tightness in the chest
  4. wheezing

Get emergency help immediately if any of the following symptoms of overdose occur:

Symptoms of overdose

  1. Anxiety
  2. chest pain or discomfort
  3. dizziness
  4. dry mouth
  5. fainting
  6. fast, slow, or irregular heartbeat
  7. hyperventilation
  8. irregular heartbeats
  9. irritability
  10. lightheadedness
  11. nervousness
  12. pounding or rapid pulse
  13. restlessness
  14. seeing, hearing, or feeling things that are not there
  15. shaking
  16. trouble with sleeping

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

  1. Abdominal or stomach pain
  2. acid or sour stomach
  3. belching
  4. continuing ringing or buzzing or other unexplained noise in the ears
  5. diarrhea
  6. difficulty with concentrating
  7. headache
  8. hearing loss
  9. heartburn
  10. impaired concentration
  11. indigestion
  12. lack or loss of strength
  13. loss of appetite
  14. nausea
  15. rash
  16. shakiness and unsteady walk
  17. sleepiness or unusual drowsiness
  18. stomach discomfort, upset, or pain
  19. unsteadiness, trembling, or other problems with muscle control or coordination
  20. unusual tiredness or weakness
  21. vomiting

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Portions of this document last updated: Feb. 01, 2024

Original article: https://www.mayoclinic.org/drugs-supplements/rimantadine-oral-route/side-effects/drg-20065846