Drug Name

Symmetrel (amantadine)

Drug Uses

Amantadine is an antiviral medication. It blocks the actions of viruses in your body.

Amantadine is used to treat and to prevent influenza A (a viral infection). There may be some flu seasons during which amantadine is not recommended because certain flu strains may be resistant to this drug.

Amantadine is also used to treat Parkinson's disease and "Parkinson-like" symptoms such as stiffness and shaking that may be caused by the use of certain drugs.

Amantadine may also be used for other purposes not listed in this medication guide.

How to use

Take this medication exactly as it was prescribed for you. Do not take the medication in larger amounts, or take it for longer than recommended by your doctor. Follow the directions on your prescription label.

Take this medicine with a full glass of water.
Measure the liquid form of amantadine with a special dose-measuring spoon or cup, not a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.

If you are taking amantadine to treat influenza A, start taking the medication within 24 to 48 hours after flu symptoms begin. Keep taking the medication for the entire length of time prescribed by your doctor. Your symptoms may get better before the infection is completely treated. If you are taking amantadine to treat Parkinson symptoms, do not stop taking the medication without first talking to your doctor. If you stop taking amantadine suddenly, your condition may become worse. Store amantadine at room temperature away from moisture and heat.

Drug Class and Mechanism

Symmetrel is designated generically as amantadine hydrochloride and chemically as 1-adamantanamine hydrochloride.

Missed Dose

Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the medicine at the next regularly scheduled time. Do not take extra medicine to make up the missed dose.

Storage

Store this medicine at room temperature in a tightly-closed container, away from heat and light.

Warnings/Precautions

Do not use FluMist nasal influenza "live vaccine" while you are being treated with amantadine and for at least 48 hours after you stop taking amantadine. The nasal vaccine may not be as effective if you receive it while you are taking amantadine. Before taking amantadine, tell your doctor if you have received a nasal flu vaccine within the past 14 days.

Before taking amantadine, tell your doctor if you have epilepsy or other seizure disorder, congestive heart failure, kidney or liver disease, low blood pressure, eczema, glaucoma, or a history of mental illness, suicide attempt, or drug/alcohol addiction.

Amantadine can cause side effects that may impair your thinking, vision, or reactions. Be careful if you drive or do anything that requires you to be alert and able to see clearly. If you are taking amantadine to treat influenza A, take the medication for the entire length of time prescribed by your doctor. Your symptoms may get better before the infection is completely treated. If you are taking amantadine to treat Parkinson symptoms, do not stop taking the medication without first talking to your doctor. If you stop taking amantadine suddenly, your condition may become worse.

You may have increased sexual urges, unusual urges to gamble, or other intense urges while taking this medication. Talk with your doctor if you believe you have any intense or unusual urges while taking amantadine.

Before taking amantadine, tell your doctor if you are using any of the following drugs:

• atropine (Atreza, Sal-Tropine, and others);
• dicyclomine (Bentyl);
• glycopyrrolate (Robinul);
• hyoscyamine (Anaspaz, Levbid, Levsin, Nulev, and others);
• mepenzolate (Cantil);
• methscopolamine (Pamine);
• propantheline (Pro-Banthine);
• scopolamine (Maldemar, Scopace, Transderm-Scop).
• quinine (Qualaquin);
• quinidine (Cardioquin, Quinaglute);
• a diuretic (water pill) such as triamterene (Dyrenium), hydrochlorothiazide (HCTZ, Dyazide, HydroDiuril, Hyzaar, Lopressor, Vasoretic, Zestoretic), and others; or
• phenothiazines such as prochlorperazine (Compazine), thioridazine (Mellaril), and others.

Possible Side Effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Call your doctor at once if you have any of these serious side effects:

• feeling short of breath, even with mild exertion;
• swelling, rapid weight gain;
• feeling depressed, agitated, or aggressive;
• behavior changes, hallucinations, thoughts of hurting yourself;
• urinating less than usual or not at all;
• high fever, stiff muscles, confusion, sweating, fast or uneven heartbeats, rapid breathing, feeling like you might pass out;
• restless muscle movements in your eyes, tongue, jaw, or neck; or
• tremor (uncontrolled shaking).

• dizziness, drowsiness, headache;
• sleep problems (insomnia), strange dreams;
• feeling nervous;
• nausea, diarrhea, constipation, loss of appetite;
• dry mouth, dry nose; or
• loss of balance or coordination.

More Information

Do not use FluMist nasal influenza "live vaccine" while you are being treated with amantadine and for at least 48 hours after you stop taking amantadine. The nasal vaccine may not be as effective if you receive it while you are taking amantadine. Before taking amantadine, tell your doctor if you have received a nasal flu vaccine within the past 14 days. Amantadine can cause side effects that may impair your vision, thinking, or reactions. Be careful if you drive or do anything that requires you to be alert and able to see clearly.

Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall. Avoid drinking alcohol. It can increase some of the side effects of amantadine.

Avoid taking diet pills, caffeine pills, or other stimulants (such as ADHD medications) without your doctor's advice. Taking a stimulant together with amantadine can increase your risk of unpleasant side effects.