Symmetrel (Oral)

Amantadine is a medicine that helps control movements. It is used to treat Parkinson's disease (sometimes called "paralysis agitans" or "shaking palsy") and symptoms like dyskinesia (sudden uncontrolled movements). It can be taken alone or with other medicines (for example, levodopa) for Parkinson's disease. By improving muscle control and reducing stiffness, this medicine helps you move more normally as symptoms of the disease are lessened. Amantadine is also used to treat stiffness and shakiness caused by certain medicines used for nervous, mental, and emotional conditions.

Amantadine is also an antiviral medicine. It is used to prevent or treat certain types of influenza (flu) infections (type A). It can be taken alone or with flu shots. Amantadine will not work for colds, other types of flu, or other viral infections.

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

It is very important that your doctor checks your progress at regular visits to see if the medicine is working properly and to allow changes in your dose. Blood and urine tests may be needed to check for any unwanted effects.

Amantadine may cause some people to feel agitated, irritable, or show other unusual behaviors. It may also lead to some people having suicidal thoughts and tendencies or becoming more depressed. Tell your doctor if you have sudden or strong feelings, such as feeling nervous, angry, restless, violent, or scared. If you, your child, or your caregiver notice any of these side effects, tell your doctor or your child's doctor immediately.

Some people who have used this medicine experienced unusual changes in their behavior. Speak with your doctor right away if you start having unusual urges, such as urges to gamble, binge or compulsive eating, compulsive shopping, or sexual urges while using this medicine.

Drinking alcohol while taking this medicine may increase side effects, such as circulation problems, dizziness, lightheadedness, fainting, or confusion. Do not drink alcohol while you are taking this medicine.

This medicine may cause some people to feel dizzy, drowsy, or lightheaded, or to have blurred vision or trouble concentrating. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.

Dizziness, lightheadedness, or fainting may occur with this medicine, especially when you suddenly get up from lying or sitting down. These symptoms are more likely to happen when you start taking this medicine or when the dose is increased. Getting up slowly may help. If this problem continues or gets worse, check with your doctor.

Patients with Parkinson's disease must be careful not to overdo physical activities when their condition improves and movements become easier, as injuries from falls may occur. These activities should be gradually increased to allow your body time to adjust to changes in balance, circulation, and coordination.

Amantadine may cause dryness of the mouth, nose, and throat. For temporary relief of mouth dryness, use sugarless candy or gum, melted bits of ice in your mouth, or a saliva substitute. If your mouth continues to feel dry for more than 2 weeks, check with your doctor or dentist. Ongoing dryness of the mouth may increase the risk of dental disease, including tooth decay, gum disease, and fungal infections.

This medicine may cause purplish red, net-like, blotchy spots on the skin. This issue occurs more often in females and usually appears on the legs or feet after this medicine has been taken regularly for a month or more. Although the blotchy spots may last as long as you are taking this medicine, they will usually fade gradually within 2 to 12 weeks after stopping the medicine. If you have any questions about this, talk with your doctor.

Check with your doctor immediately if you experience convulsions (seizures), difficulty breathing, a fast heartbeat, a high fever, high or low blood pressure, increased sweating, loss of bladder control, severe muscle stiffness, unusually pale skin, or extreme tiredness. These could be symptoms of a serious condition called neuroleptic malignant syndrome (NMS).

If you are using this medicine for Parkinson's disease, do not stop taking it suddenly without first consulting your doctor. Your doctor may want you to slowly reduce the amount you are taking before stopping it completely.

If you are using this medicine for Parkinson's disease, it is important that your doctor checks your skin regularly for signs of melanoma (skin cancer). If you notice any unusual red, brown, or black spots on your skin, contact your doctor immediately.

If your Parkinson's symptoms do not improve within a few days, worsen, or if this medicine seems less effective after a few weeks, consult your doctor.

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

In deciding to use a medicine, you and your doctor need to weigh the risks against the benefits. For this medicine, the following should be considered:

Allergies

Inform your doctor if you have ever had any unusual or allergic reactions to this medicine or any other medicines. Also, let your healthcare professional know if you have any other allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, carefully read the label or package ingredients.

Pediatric

Appropriate studies have not been done on how Gocovri® and Osmolex ER™ affect children. Safety and effectiveness have not been established for this age group.

Geriatric

Studies so far have not shown any specific problems in older adults that would limit the usefulness of amantadine. However, older patients may be more likely to experience unwanted effects (e.g., falls, hallucinations) and age-related kidney issues, requiring caution when using Gocovri® and Osmolex ER™.

Breast Feeding

There are no adequate studies in women to determine the risk to infants when using this medication during breastfeeding. Consider the potential benefits and risks before taking this medication while nursing.

Interactions with Medicines

Some medicines should not be used together at all, while others may be used together even if interactions could happen. In these cases, your doctor may adjust the dose or take other precautions. When taking this medicine, it is especially important for your healthcare professional to know if you are using any of the medicines listed below. The following interactions are significant and not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or adjust the other medicines you take.

• Potassium Citrate

Using this medicine with any of the following medicines is usually not recommended, but may be necessary in some cases. If both medicines are prescribed together, your doctor may adjust the dose or frequency of use for one or both medicines.

• Aclidinium
• Amifampridine
• Amitriptyline
• Amoxapine
• Atropine
• Belladonna
• Benztropine
• Biperiden
• Brompheniramine
• Buprenorphine
• Bupropion
• Carbinoxamine
• Carisoprodol
• Chlorpheniramine
• Chlorpromazine
• Clemastine
• Clidinium
• Clomipramine
• Clozapine
• Codeine
• Cyclobenzaprine
• Cyclopentolate
• Cyproheptadine
• Darifenacin
• Desipramine
• Dicyclomine
• Dimenhydrinate
• Diphenhydramine
• Donepezil
• Doxepin
• Fesoterodine
• Flavoxate
• Fluphenazine
• Glucagon
• Glycopyrrolate
• Glycopyrronium Tosylate
• Homatropine
• Hydroxyzine
• Hyoscyamine
• Imipramine
• Ipratropium
• Loxapine
• Meclizine
• Memantine
• Mepenzolate
• Methacholine
• Metoclopramide
• Nortriptyline
• Olanzapine
• Orphenadrine
• Oxitropium Bromide
• Oxybutynin
• Oxycodone
• Paroxetine
• Perphenazine
• Pimozide
• Pipenzolate Bromide
• Pirenzepine
• Prochlorperazine
• Procyclidine
• Promethazine
• Propantheline
• Propiverine
• Protriptyline
• Quetiapine
• Scopolamine
• Secretin Human
• Solifenacin
• Stramonium
• Tapentadol
• Terodiline
• Thiothixene
• Tiotropium
• Tizanidine
• Tolterodine
• Trifluoperazine
• Trihexyphenidyl
• Trimipramine
• Tropicamide
• Trospium
• Umeclidinium

Using this medicine with any of the following medicines may increase the risk of certain side effects, but using both drugs may be necessary for your treatment. If both medicines are prescribed together, your doctor may adjust the dose or frequency of use for one or both medicines.

• Betel Nut
• Bromperidol
• Triamterene
• Trimethoprim

Interactions with Food/Tobacco/Alcohol

Some medicines should not be taken around the time of eating food or certain types of food because interactions may occur. Using alcohol or tobacco with some medicines can also cause interactions. The following interactions are significant and not necessarily all-inclusive.

Other Medical Problems

Other medical issues may affect how this medicine works. Make sure to inform your doctor if you have any other medical problems, especially:

• Congestive heart failure or
• Eczema, recurrent, history of or
• Epilepsy or seizures, history of or
• Hypotension (low blood pressure) or
• Liver disease or
• Neuroleptic malignant syndrome (NMS), history of or
• Peripheral edema (swelling of the hands, ankles, or feet) or
• Psychosis (mental illness), history of or
• Sleeping disorder—Use with caution. May worsen these conditions.

• End-stage kidney disease or
• Glaucoma, angle-closure, untreated (narrow-angle glaucoma)—Should not be used in patients with these conditions.

• Kidney disease—Use with caution. This medicine's effects may be stronger due to slower removal from the body.

Along with its needed effects, a medicine may cause some unwanted effects. Not all of these side effects may happen, but if they do, they may need medical attention.

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

More common

• Bladder pain
• Bloody or cloudy urine
• Blurred vision
• Confusion
• Difficult, burning, or painful urination
• Dizziness or lightheadedness
• Fainting
• Falls
• Frequent urge to urinate
• Lower back or side pain
• Seeing, hearing, or feeling things that are not there
• Swelling of the hands, feet, or lower legs

Less common

• Inability to move the eyes
• Increased blinking or spasms of the eyelid
• Muscle spasm
• Sticking out of the tongue
• Trouble breathing, speaking, or swallowing
• Uncontrolled twisting movements of the neck, trunk, arms, or legs
• Unusual facial expressions

Rare

• Chills
• Decreased vision or any change in vision
• Difficulty in coordination
• Fever
• Increased blood pressure
• Increase in body movements
• Irritation and swelling of the eye
• Loss of memory
• Mental depression
• Seizures
• Severe mood or mental changes
• Skin rash
• Slurred speech
• Sore throat
• Thoughts of suicide or attempts at suicide

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. Your healthcare professional may also be able to tell you ways to prevent or reduce some of these side effects. Check with your healthcare professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

• Agitation
• Anxiety
• Difficulty concentrating
• Dry mouth
• Headache
• Irritability
• Loss of appetite
• Nausea
• Nervousness
• Nightmares
• Purplish red, net-like, or blotchy spots on the skin
• Trouble with sleeping

Less common

• Blindness
• Blurred vision
• Constipation
• Decrease in sexual desire
• Decreased vision
• Diarrhea
• Drowsiness
• Dry eyes
• Dryness of the mouth, nose, and throat
• False sense of well-being
• Joint swelling
• Unusual tiredness or weakness
• 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.

In the U.S.

• Gocovri
• Osmolex ER
• Symmetrel

Available Dosage Forms:

• Tablet, Extended Release
• Capsule, Liquid Filled
• Tablet
• Solution
• Syrup
• Capsule
• Capsule, Extended Release

Therapeutic Class: Antiparkinsonian

Pharmacologic Class: Anticholinergic

Chemical Class: Adamantane

For patients taking amantadine for Parkinson's disease or movement problems (including dyskinesia) caused by certain medicines used to treat nervous, mental, and emotional conditions:

• Take this medicine exactly as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.
• This medicine comes with a Medication Guide or patient information leaflet. Read and follow these instructions carefully. Ask your doctor if you have any questions.
• Do not stop using this medicine suddenly without asking your doctor. You may need to slowly decrease your dose before stopping it completely.
• Improvement in the symptoms of Parkinson's disease usually occurs in about 2 days. However, in some patients, this medicine must be taken for up to 2 weeks before the full benefit is seen.

For patients taking amantadine to prevent or treat flu infections:

• 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 right away 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. Or 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 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 2 days after all your flu symptoms have disappeared.
• 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 at day and night. For example, if you are to take two doses a day, the doses should be spaced about 12 hours apart. If this interferes with your sleep or other daily activities, or if you need help in planning the best times to take your medicine, check with your doctor.
• If you are using the oral liquid form of amantadine, use a marked measuring spoon, oral syringe, or medicine cup to measure each dose correctly. The average household teaspoon may not hold the right amount of liquid.

Take Gocovri® extended-release capsule at bedtime. Swallow whole. Do not crush, break, or chew it. You may also open and sprinkle the extended-release capsules on a teaspoonful of soft food, including applesauce. Take all of the medicine right away without chewing. You may take this medicine with or without food.

Take Osmolex ER™ extended-release tablet in the morning. Swallow whole. Do not crush, open, or chew it.

Do not receive the nasal flu vaccine (live attenuated influenza vaccine) while taking this medicine.

Do not drink alcohol while you are using this medicine.

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 treatment of Parkinson's disease or movement problems (including dyskinesia): For oral dosage forms (extended-release capsules): Adults—137 milligrams (mg) once a day at bedtime. Your doctor may increase your dose to 274 mg (two 137 mg capsules) once a day at bedtime after one week. Children—Use and dose must be determined by your doctor. For oral dosage forms (extended-release tablets): Adults—129 milligrams (mg) once a day in the morning. Your doctor may increase your dose each week to a maximum dose of 322 mg (one 129 mg tablet and one 193 mg tablet) once a day taken in the morning. Children—Use and dose must be determined by your doctor. For oral dosage forms (liquid-filled capsules, syrup, and tablets): Adults—100 milligrams (mg) 2 times a day. Your doctor may adjust your dose as needed. Older adults—At first, 100 milligrams (mg) once a day as a single dose. Your doctor may adjust your dose as needed. Children—Use and dose must be determined by your doctor.
• For the treatment or prevention of flu:For oral dosage forms (capsules, syrup, and tablets): Adults—200 milligrams (mg) or 4 teaspoonfuls once a day as a single dose. Older adults—100 milligrams (mg) once a day as a single dose. Children 9 to 12 years of age—100 milligrams (mg) or 2 teaspoonfuls 2 times a day. Children 1 to 9 years of age—Dose is based on body weight and must be determined by your doctor. The usual dose is 4.4 to 8.8 milligrams (mg) per kilogram (kg) of body weight per day. The dose is divided evenly and given 2 times a day. However, the dose is usually not 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.

If you miss a dose of amantidine, skip the missed dose and take your next dose at your usual time. Do not take extra medicine to make up for a missed dose.

Storage

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

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.

• What is the difference between Osmolex ER and Gocovri?
• What is Gocovri used to treat?
• Why should you not discontinue amantadine?
• Why was amantadine discontinued for flu?
• How long does it take for amantadine to start working?
• What symptoms does amantadine treat?
• What is Gocovri (amantadine) and how does it work?

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