For relief of Parkinson's disease symptoms, amantadine is usually taken once or twice daily. Short courses of amantadine can also be used to prevent the rash and pain caused by shingles infection (herpes zoster).
The most common side-effects are swollen ankles and red skin blotches. It can also cause drowsiness and blurred vision, so please take care when using tools or machines.
|Type of medicine||A dopamine agonist|
|Used for||Parkinson's disease; Prevention of shingles rash and nerve pain|
|Available as||Capsules and oral liquid medicine|
Amantadine can be prescribed to relieve the symptoms of Parkinson's disease, although other treatments are often preferred.
Parkinson's disease affects the way your brain co-ordinates the movements of your muscles. Nerve messages to the muscles become slowed and abnormal. This leads to symptoms such as shaking (tremor), muscle stiffness, and slow movement. Amantadine helps to ease these symptoms. It is usually prescribed alongside other medicines used for the treatment of Parkinson's disease.
Amantadine can also be prescribed to help lessen or prevent the rash and nerve pain that is often caused by shingles (herpes zoster). The medicine is given to people at risk of a severe or painful rash.
If you have been prescribed amantadine for any other reason, speak to your doctor or a pharmacist if you have any questions.
Before taking amantadine
Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking amantadine it is important that your doctor knows:
- If you are pregnant or breastfeeding.
- If you have any problems with the way your liver works, or any problems with the way your kidneys work.
- If you have a heart condition.
- If you have fits, or epilepsy.
- If you have increased pressure in your eyes (glaucoma).
- If you have ever had a stomach ulcer.
- If you feel confused, or if you see or hear things that are not real (hallucinations).
- If you have ever had an allergic reaction to a medicine.
- If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.
How to take amantadine
- Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack and any additional information your doctor has given to you. These will give you more information about amantadine and will provide you with a full list of the side-effects which you may experience from taking it.
- Take amantadine exactly as your doctor tells you to.
- If you have been prescribed amantadine for Parkinson's disease symptoms it is usual to take 100 mg daily (one capsule or two 5 ml spoonfuls) for the first week, and then for the dose to increase to twice a day. Some people may require doses of up to 400 mg daily.
- If you have been prescribed amantadine to prevent a shingles rash and nerve pain (postherpetic neuralgia) the dose is 100 mg twice a day for 14 days. If you are still in pain after 14 days a further course of treatment may be prescribed.
- Your doctor or pharmacist will tell you what dose to take each day, and the directions will also be printed on the label of the pack to remind you about what the doctor said to you.
- Try to take your doses of amantadine at the same time(s) each day, as this will help you remember to take it regularly.
- If you forget to take a dose, take it as soon as you remember. Try to take the correct number of doses each day but do not take two doses together to make up for a missed dose.
Getting the most from your treatment
- Sometimes people taking medicines like amantadine can fall asleep suddenly with little or no warning of being tired beforehand. Until you know how you react, take extra care if you operate machinery or drive. If you do find yourself falling asleep suddenly, you should see your doctor as soon as possible for advice, and avoid driving or using tools and machines in the meantime.
For people with Parkinson's disease
- Try to keep your regular appointments with your doctor. This is so your doctor can check on your progress. During the first few weeks of treatment in particular, your dose may require adjusting.
- Stay as active as possible and exercise regularly as much as you are able. You may walk more slowly than before but a daily walk is good exercise and may help to loosen up stiff muscles.
- If you are a driver you should tell the DVLA and your insurance company that you have Parkinson's disease. Depending on the severity of symptoms and the medicines that you are taking, you may still be allowed to drive following a medical assessment.
- Treatment with medicines for Parkinson's disease can sometimes cause problems with impulsive types of behaviour. If you notice any changes in your behaviour, such as an increased desire to gamble, binge eat, or spend excessively, or an increased sex drive, you must let your doctor know as soon as possible.
- Continue to take amantadine regularly. Stopping treatment suddenly can cause serious problems. Your doctor will probably want you to reduce your dose gradually if this becomes necessary.
Can amantadine cause problems?
Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the common ones associated with amantadine. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.
|Very common amantadine side-effects (these affect more than 1 in 10 people)||What can I do if I experience this?|
|Swollen ankles, red skin blotches||If troublesome, speak with your doctor|
|Common amantadine side-effects (these affect fewer than 1 in 10 people)||What can I do if I experience this?|
|Loss of appetite, feeling sick (nausea), constipation||Eat a well-balanced diet and drink plenty of water|
|Blurred vision; feeling dizzy, light-headed or tired||Do not drive and do not use tools or machines while affected. Do not drink alcohol|
|Dry mouth||Try chewing sugar-free gum or sucking sugar-free sweets|
|Headache, muscle pain||Drink plenty of water and ask your pharmacist to recommend a suitable painkiller. If the headaches continue, let your doctor know|
|Feeling anxious or confused, changes in your mood, difficulties sleeping, lack of concentration, slurred speech, a fast heartbeat, increased sweating, hearing or seeing things that are not real (hallucinations)||If any of these become troublesome, speak with your doctor|
If you experience any other symptoms which you think may be due to amantadine, speak with your doctor or pharmacist for further advice.
How to store amantadine
- Keep all medicines out of the reach and sight of children.
- Store in a cool, dry place, away from direct heat and light.
- The oral liquid medicine will keep for one month after first opening. Do not use any remaining medicine after this time. It is a good idea to write the date you opened the bottle on the label.
Important information about all medicines
Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.
If you are having an operation or any dental treatment, tell the person carrying out the treatment which medicines you are taking.
This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.
If you buy any medicines, always check with a pharmacist that they are safe to take with your other medicines.
Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.
If you have any questions about this medicine ask your pharmacist.
Further reading and references
Manufacturer's PIL, Amantadine hydrochloride 100 mg capsules; Alliance Pharmaceuticals, The electronic Medicines Compendium. Dated January 2021.
Manufacturer's PIL, Amantadine hydrochloride 50 mg/5 ml oral solution; Northumbria Pharma Ltd, The electronic Medicines Compendium. Dated November 2020.
Medicines Complete BNF 86th Edition; British Medical Association and Royal Pharmaceutical Society of Great Britain, London.