Symmetrel (Amantadine)

Indications

Amantadine is an antiviral medication that can be used to prevent or treat Influenza. It is a brand name for the drug amantadine hydrochloride. If you have been infected with Influenza, it can help alleviate your symptoms and shorten the time it takes to recover. It works by blocking the actions of viruses in the body and by restoring the balance of natural substances in the brain.

Symmetrel can also be used to treat Parkinson's disease and drug-induced extrapyramidal symptoms, as well as side effects caused by chemicals and other medical conditions. When used to treat these conditions, amantadine may help improve your range of motion and ability to exercise. It is thought to restore the balance of natural chemicals (neurotransmitters) in the brain, which can help alleviate these symptoms.

Uses and Dosage

Symmetrel capsules should be taken orally with or without food, as directed by your doctor, usually once or twice daily. If you have trouble sleeping after taking Symmetrel capsules twice daily, take the second dose several hours before bedtime. Dosage of Symmetrel is based on your medical condition and response to therapy, and in children, it is based on body weight. Be sure to follow your doctor's instructions, and do not take more than prescribed.

To ensure the medication is effective, maintain a constant level of Symmetrel in your body. Take the capsules at even intervals throughout the day and night. If taking Symmetrel for a viral infection, begin taking it as soon as possible and continue for the full prescribed amount, even if symptoms disappear after a few days. Stopping the medication too early may result in relapse of the infection.

With Parkinson's disease, Symmetrel may take several weeks to show effects. Do not stop taking the medication suddenly, as this may worsen your symptoms or side effects. Your doctor may gradually reduce your dose instead. After several months of use, the capsules may not work as well. Be sure to inform your doctor if this happens.

Side effect

Common Side Effects of Symmetrel (Amantadine):

• Constipation
• Dizziness
• Dry mouth
• Falls
• Nausea
• Sleep problems (insomnia)
• Swelling in your legs or feet

Serious Side Effects of Symmetrel (Amantadine):

• Aggression
• Agitation
• Behavior changes
• Confusion
• Depression
• Difficulty breathing
• Extreme drowsiness
• Falling asleep suddenly even after feeling alert
• Fast or uneven heartbeats
• Hallucinations
• High fever
• Hives
• Lightheadedness
• Painful or difficult urination
• Seizure
• Shortness of breath
• Sweating
• Swelling in your hands or feet
• Swelling of your face lips tongue or throat
• Thoughts or hurting yourself
• Tremors
• Very stiff (rigid) muscles

Form and Strength

Symmetrel (Amantadine) is available in the following forms and strength:

Symmetrel: Capsule

• 100 mg

Amantadine: Capsule

• 100 mg

Caution

• Caution should be observed when prescribing Symmetrel to patients being treated with drugs having central nervous system (CNS) effects as it may increase the risk of adverse effects.
• Symmetrel should be used with caution in patients with a history of seizures as it may lower the seizure threshold and increase the risk of seizures.
• The use of Symmetrel in patients with liver or kidney disease may require dosage adjustment as the drug is eliminated primarily through the kidneys and liver.
• The use of Symmetrel in elderly patients may require caution as they may be more sensitive to the drug's effects.
• Symmetrel may cause dizziness or lightheadedness and caution should be taken when driving or operating machinery.
• Symmetrel may cause psychiatric symptoms such as hallucinations, confusion and depression and caution should be taken in patients with a history of psychiatric illness.
• Symmetrel may interact with other medications so inform your doctor of all medications you are taking before starting Symmetrel.
• Symmetrel may cause blood pressure changes and caution should be taken in patients with a history of hypertension or hypotension.
• Patients with a history of congestive heart failure or peripheral edema should be monitored closely while taking Symmetrel as it may exacerbate these conditions.
• Symmetrel should be used with caution in patients with a history of eczema or other skin disorders as it may worsen these conditions.
• Symmetrel may cause dry mouth or constipation and caution should be taken in patients with a history of these symptoms.
• Symmetrel should not be used in patients with a known hypersensitivity to the drug or its components.
• Symmetrel may cause an allergic reaction and patients should be monitored for signs of an allergic reaction such as rash or hives.
• Symmetrel should not be used in pregnant or nursing mothers unless the benefits outweigh the risks.

Frequently Asked Questions (FAQ)

How is Symmetrel dosed?

Symmetrel is usually taken once or twice daily as directed by a healthcare professional. The dosage may need to be adjusted in patients with liver or kidney disease.

Can Symmetrel be stopped abruptly?

Abruptly stopping Symmetrel may cause withdrawal symptoms or worsening of symptoms. Work with a healthcare provider to gradually taper and discontinue the medication as directed.

Can Symmetrel cause weight gain?

Weight gain is not a common side effect of Symmetrel, but it may occur in some patients.

How long does it take for Symmetrel to work?

The onset of action of Symmetrel may vary depending on the condition being treated. Low the dosing instructions provided by a healthcare provider and to allow sufficient time for the medication to take effect.

Are there any foods or drugs that interact with Symmetrel?

Symmetrel may interact with certain foods or drugs, so discuss all medications and supplements being taken with a healthcare provider before starting Symmetrel.

Resources

• https://www.accessdata.fda.gov/drugsatfda_docs/label/2009/016023s041018101s016lbl.pdf
• https://www.webmd.com/drugs/2/drug-1239/symmetrel-oral/details
• https://www.news-medical.net/drugs/Symmetrel.aspx
• https://www.rxlist.com/symmetrel-drug.htm
• https://www.drugs.com/mtm/symmetrel.html
• https://www.everydayhealth.com/drugs/amantadine