Symmetrel is an antiviral medication. It blocks the actions of viruses in your body. It is used to prevent or treat a certain type of flu (influenza A). If you have been infected with the flu, this medication may help make your symptoms less severe and shorten the time it will take you to get better. Symmetrel is also used to treat Parkinson's disease, as well as side effects caused by drugs (drug-induced extrapyramidal symptoms), chemicals, other medical conditions.
Take Symmetrel exactly as prescribed by your doctor. The recommended dose for treating or preventing the flu in adults is 100 mg twice daily or 200 mg once daily. Taking it twice a day may decrease the chance of side effects. A lower dose (100 mg once daily) is recommended for people age 65 years or older. For children age 9 and older, the recommended dose is 100 mg twice daily. For flu treatment, Symmetrel should be started as soon as possible within 24 to 48 hours of the start of flu symptoms, and it should be continued for 24 to 48 hours after the symptoms go away.
For treating Parkinson's disease the recommended dose is 100 mg twice a day, if no other Parkinson's medications are used. Your doctor may increase your dose up to a maximum of 400 mg total per day.
The recommended dose for treating extrapyramidal symptoms caused by other medications is 100 mg twice daily. Your doctor may increase your dose up to a total of 300 mg per day.
If you have liver or kidney disease, your doctor may recommend a low dose. You can take Symmetrel with or without food.
Before taking Symmetrel you should talk with your doctor if you have psychiatric disorder, substance abuse, congestive heart failure, glaucoma, low blood pressure (hypotension), swelling in the hands, feet, or ankles, seizures, epilepsy, liver disease, liver failure, cirrhosis, hepatitis, kidney disease, kidney failure, eczema, any allergies. This drug may make you dizzy or drowsy or cause blurred vision. Do not drive or perform tasks that require alertness. Avoid alcoholic beverages. Alcohol can increase some of the side effects. Avoid taking diet pills, caffeine pills, or other stimulants. Taking a stimulant together with amantadine can increase your risk of unpleasant side effects. To minimize dizziness and lightheadedness, get up slowly when rising from a seated or lying position. Elderly people may be at a greater risk for side effects while taking this drug.
You should not take Symmetrel if you are allergic to it, amantadine hydrochloride, or any of the inactive components of the medication, are pregnant or breastfeeding.
Possible side effect
Get emergency medical help if you have blurred vision, nausea, stomach upset, drowsiness, dizziness, headache, dry mouth, constipation, nervousness, trouble sleeping, hives, swelling of your face, lips, tongue, difficulty breathing, stiff muscles, rapid weight gain, tremor. If you notice other effects not listed above, contact your doctor.
Tell your doctor about all other medications you use, especially: phenothiazines (thioridazine, prochlorperazine), diuretics (hydrochlorothiazide, triamterene), anticholinergic medications (benztropine, scopolamine, haloperidol, dicyclomine), antipsychotic medications (chlorpromazine, thiothixene, loxapine), quinidine, mepenzolate, glycopyrrolate, atropine, dicyclomine. Interaction between two medications does not always mean that you must stop taking one of them. Tell your doctor or prescriber about all prescription, over-the-counter, and herbal medications you are taking.
Take the missed dose as soon as possible. Skip the missed dose if it is time for your next scheduled dose. Don't take extra medicine to make up the missed dose.
If you think you have overdosed the medicine seek emergency medical help at once. The overdose symptoms are fast or irregular heartbeats, severe drowsiness, shortness of breath, urinating less than usual, mental or mood changes, anxiety, aggression, confusion, hallucinations, seizures, fainting.
Store the medicine at room temperature between 59-77 degrees F (15-25 degrees C) away from light and moisture. Do not store the drugs in the bathroom. Keep all drugs away from reach of children and pets.
The information presented at the site has a general character. Note please this information cannot be used for self-treatment and self diagnosis. You should consult with your doctor or health care adviser regarding any specific instructions of your condition. The information is reliable, but we concede it could contain mistakes. We are not responsible for any direct, indirect, special or other damage caused by use of this information on the site and also for consequences of self-treatment.