Experiences with

Memantine

Memantine is a medicine for dementia. It is used to treat memory loss which is one of the main symptoms of dementia.

It is also used to treat the symptoms of:

• Alzheimer's disease
• dementia with Lewy bodies
• mixed dementia – when you have more than one type of dementia
• corticobasal degeneration (CBD)

Memantine does not work for everyone. It is not a cure for dementia and your symptoms may gradually get worse, even when you're taking it.

How each person responds to memantine will be different. Some people find it helps with their symptoms a lot. For others, it might seem like it's not working, but it could be preventing symptoms from getting worse.

Memantine is available on prescription only. It comes as tablets, including soluble tablets that you dissolve in water and swallow as a drink, tablets that melt in your mouth, and as a liquid that you swallow.

Who can take memantine

Most adults aged 18 years and over can take memantine.

Who may not be able to take memantine

Memantine is not suitable for some people. To make sure it's safe, tell your doctor if you, or the person you're caring for, have:

• ever had an allergic reaction to memantine or any other medicine
• epilepsy or have ever had a seizure or fit
• ever had a heart attack
• heart failure
• high blood pressure
• kidney or liver problems

Dosage and strength

Memantine comes as 5mg, 10mg, 15mg and 20mg tablets. It also comes as a liquid (oral solution) that you swallow, containing 10mg in 1ml.

The starting dose is:

• one 5mg tablet, once a day. This is usually increased by 5mg every week until your dose is 20mg. You may get a starter pack containing 7 tablets of each strength to help you increase your dose
• one 0.5ml dose of memantine liquid, once a day. This is usually increased by 0.5ml every week until your dose is 2ml (20mg)

How to take it

Take your memantine dose at the same time each day.

Standard tablets

Swallow your standard memantine tablet whole with a drink of water.

Dissolvable tablets

Memantine also comes as a tablet that melts in your mouth (orodispersible tablet). Put the tablet on your tongue and let it dissolve until it has gone. You can have a drink of water afterwards if you need to.

Soluble tablets

Dissolve your tablet in half a cup of water and drink it straight away.

Liquid

Memantine liquid comes in a pump dispenser (which pumps out your dose) or in a bottle with a syringe.

How to use the pump dispenser

Press the pump down 1, 2, 3 or 4 times depending on your dose. One pump gives 0.5ml and 4 pumps give a 2ml dose.

Pump the medicine onto a spoon or into a small glass of water. Do not pour or pump the medicine straight into your mouth.

How to use the syringe

If your memantine liquid comes in a bottle with a syringe rather than a pump:

1. Push the syringe into the bottle neck and turn the bottle upside down.
2. Fill the syringe to the right dose, turn the bottle the right way up and remove the syringe.
3. Squirt the medicine onto a spoon, into a small glass of water or straight into your mouth. Swallow your dose straight away. Have a drink of water afterwards if you need to.
4. Wash the syringe and let it dry before you use it again.

How long to take it for

You'll keep taking memantine unless your doctor tells you to stop.

You, or the person you are caring for, will have regular check-ups with a doctor to see whether memantine is still helping and if you should keep taking it.

Only stop taking memantine if your doctor tells you to. If you stop, your symptoms may come back or get worse.

If you forget to take it

If you forget a dose of memantine, skip the missed dose and take the next one at the usual time.

Do not take 2 doses to make up for a forgotten dose.

If you forget doses often, it may help to set an alarm to remind you. You could also ask a doctor, pharmacist or dementia support group for advice on other ways to help you remember to take your medicine.

When you start taking memantine, you will increase your dose over a few weeks to help avoid side effects. If you forget to take these doses speak to your doctor.

If you take too much

It is very unlikely that taking 1 or 2 extra doses will cause any problems.

you've taken more than your prescribed dose of memantine and you:

• have hallucinations (seeing or hearing things that are not real)
• pass out or have a seizure or fit

• you take more than your prescribed dose of memantine and start to get any symptoms
• you've taken more than your prescribed dose of memantine and you have vomiting or diarrhoea

Get help from 111 online or call 111

If you need to go to A&E, do not drive. Ask someone to drive you or call 999 and ask for an ambulance.

Bring the memantine packet or leaflet inside it, any remaining medicine, and any other medicines you take.

Common side effects

These common side effects of memantine happen in more than 1 in 100 people. There are things you can do to help cope with them:

Talk to a doctor if these effects bother you or do not get better.

Serious side effects

Call a doctor or call 111 straight away if:

• the whites of your or eyes turn yellow, or your skin turns yellow, although this may be less obvious on black or brown skin, or if you have pale poo and dark pee – these can be signs of liver problems
• you get swollen ankles and legs, become breathless after activity or at rest, feel tired most of the time and find exercise exhausting, develop a persistent cough or a fast heart rate – these can be signs of heart failure
• you have hallucinations (hearing, seeing, smelling or tasting things that feel real but are not real) – this could be a sign of psychosis
• you get a sudden, severe pain in the centre of your stomach, feel sick or start to be sick, get diarrhoea or a high temperature – these can be signs of pancreatitis
• you get a throbbing or cramping pain, swelling, redness and warmth in your leg or arm – these can be signs of a blood clot

• or the person you're caring for, has a seizure or fit
• get a sharp chest pain (which may get worse when you breath in)
• have sudden breathlessness, difficulty breathing or coughing up blood – these can be signs of a blood clot in your lung

In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to memantine.

These are not all the side effects of memantine. For a full list, see the leaflet inside your medicine packet.

Memantine and pregnancy

Memantine is not recommended during pregnancy because there is no information about its effects.

If you take memantine and are trying to get pregnant or are already pregnant, talk to your doctor about whether it is right for you. Do not stop taking your medicine without speaking to your doctor.

Memantine and breastfeeding

There is no information about the effects of taking memantine while breastfeeding, so it is not recommended.

If you are already taking memantine and are breastfeeding, or planning to breastfeed, talk to your doctor or pharmacist.

Do not stop your medicine without speaking to your doctor first.

Memantine and fertility

There's no evidence to suggest that taking memantine reduces fertility in either men or women.

Cautions with other medicines

Some medicines do not mix well with memantine. They can increase the risk of side effects or stop memantine working as well as it should.

Tell your doctor if you or the person you're caring for is taking:

• amantadine, a medicine used for Parkinson's disease and multiple sclerosis
• ketamine, for depression or severe pain
• dextromethorphan, used in cough mixtures
• warfarin, a medicine used to help prevent blood clots
• medicines for mental health conditions such as chlorpromazine, haloperidol or olanzapine

Also tell the hospital if you, or the person you're caring for, is due to have an operation and needs to be put to sleep (have a general anaesthetic).

These are not all the medicines that affect the way memantine works. Check the leaflet inside your medicine packet to find out more.

Mixing memantine with herbal remedies and supplements

There's not enough information to say that herbal remedies and supplements are safe to take with memantine. They're not tested in the same way as pharmacy and prescription medicines. They're generally not tested for the effect they have on other medicines.

Related links

HealthUnlocked contains information from NHS Digital, licensed under the current version of the Open Government Licence