1. About co-careldopa

Co-careldopa is used to treat the main symptoms of Parkinson's disease. It can help with shaking (tremors), slowness and stiffness. These are called "motor" symptoms because they affect the way you move.

Co-careldopa is a mixture of the medicines levodopa and carbidopa. These are both used for Parkinson's disease.

It is available on prescription only. It comes as tablets, including slow-release tablets that get the medicine into your body gradually.

Duodopa gel

Co-careldopa can sometimes be used as a gel that goes through a tube into your small intestine. You will need to have surgery to have the tube fitted.

Your specialist may recommend Duodopa gel if your symptoms are difficult to manage and tablets are no longer working.

2. Key facts

  • Co-careldopa helps with motor symptoms. It does not help with non-motor symptoms such as depression or losing your sense of smell.
  • It works best if you take it 30 to 60 minutes before a meal.
  • The most common side effects of co-careldopa are feeling sick or dizzy, problems sleeping and uncontrollable jerking movements.
  • Do not stop taking this medicine suddenly. If you need to stop taking it, your doctor or specialist nurse will reduce your dose gradually.

3. Who can and cannot take co-careldopa

Co-careldopa can be taken by adults (aged 18 and above). It is sometimes prescribed for children to treat a movement disorder called dystonia.

It is not suitable for some people. To make sure co-careldopa is safe for you, tell your doctor if you:

Co-careldopa can affect the results of blood tests and urine tests. Remind your doctor that you're taking co-careldopa if you need to have any tests.

4. How and when to take it

Doses vary from person to person. Always follow the instructions from your doctor or specialist nurse.

You will usually start with a low dose. Your doctor or specialist nurse will increase your dose gradually until your symptoms are under control. It's best to take the lowest dose that controls your symptoms. This helps reduce your chance of side effects.

Do not stop taking co-careldopa suddenly. If you need to stop taking this medicine, your doctor or specialist will reduce your dose gradually. This is to prevent withdrawal symptoms.

For co-careldopa gel, this will be given under specialist care. Follow the instructions from your doctor or your specialist nurse.

Co-careldopa tablets

You will be prescribed standard-release tablets or slow-release (called "prolonged" or "controlled" release) tablets, or a combination of both.

Standard-release tablets work fairly quickly. You'll usually take these tablets several times a day, depending on your dose.

Slow-release tablets get the medicine into your body gradually. This means you do not have to take them as often.

The tablets come in different strengths. The medicine packet will show the amount of carbidopa followed by the amount of levodopa (both in milligrams).

How to take the tablets 

Take your co-careldopa at the same time each day. This is important to help control your symptoms.

Slow-release tablets are taken once or twice a day. You'll usually take standard-release tablets 3 or 4 times a day. Your doctor may recommend taking your co-careldopa more often, if you need it to control your symptoms.

It's best to take your medicine 30 to 60 minutes before you eat a meal. This is because taking it together with too much protein stops your body from absorbing the medicine properly.

Swallow the tablets whole, with a drink of water. Do not crush or chew the slow-release tablets.

If you find swallowing tablets difficult, talk to your pharmacist, doctor or specialist nurse.

What if I forget to take it? 

If you forget to take a tablet, take it as soon as you remember, unless it's nearly time for your next dose. In this case, leave out the missed dose and take your next dose as usual.

Never take 2 doses at the same time. Never take an extra dose to make up for a forgotten dose.

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

What if I take too much? 

Accidentally taking 1 or 2 extra tablets is unlikely to harm you, but talk to your doctor, specialist nurse or a pharmacist if you are concerned.

5. Side effects

Like all medicines, co-careldopa can cause side effects. However, many people have no side effects or only minor ones.

Some people notice that their pee, sweat or saliva turns a reddish colour. This is normal with co-careldopa and is not dangerous.

Common side effects

These common side effects happen in more than 1 in 100 people.

Keep taking the medicine, but talk to your doctor or pharmacist if these side effects bother you or don't go away:

  • loss of appetite, feeling or being sick (nausea or vomiting)
  • feeling dizzy when you get up from sitting or lying down
  • problems sleeping (insomnia)
  • uncontrollable twitching, twisting or writhing movements (dyskinesias)

Dyskinesias are more likely if you've been taking co-careldopa for a long time or at a high dose.

Serious side effects

It is possible to have serious side effects with co-careldopa.

Some of these side effects are rare and happen in less than 1 in 1,000 people. Others are more common.

Talk to your doctor or specialist nurse if you:

  • start gambling, binge eating or shopping uncontrollably or have an unusually high sex drive; these are signs of impulse control disorder
  • have cravings for larger doses of co-careldopa than you need to control your symptoms; these are signs of dopamine dysregulation syndrome
  • feel unusually sleepy or suddenly fall asleep during the day
  • have strange or unusual thoughts, including thinking things that are not true (delusions)
  • see things that are not there (hallucinations)
  • have mood changes, including anxiety or depression
  • are thinking about hurting yourself

Serious allergic reaction

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

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


You can report any suspected side effect to the UK safety scheme.

6. How to cope with side effects

What to do about: 

  • loss of appetite, feeling or being sick (nausea or vomiting) – having a low-protein snack (such as a plain biscuit or cracker) with your medicine may help if you're feeling or being sick. If you lose your appetite, eat when you would usually expect to be hungry. It may help to eat smaller meals, more often than usual. If you are being sick, take small sips of water to avoid dehydration.
  • feeling dizzy – if you feel dizzy when you stand up, try getting up very slowly or stay sitting down until you feel better. If you begin to feel dizzy, lie down so you do not faint, then sit until you feel better. Do not drive, cycle, or use tools or machines if you feel dizzy or tired. Do not drink alcohol as it may make you feel worse.
  • problems sleeping (insomnia) – avoid big meals, smoking, or drinking alcohol, tea or coffee in the evening. Try not to watch TV or use your mobile phone before going to bed, and relax for an hour before bedtime. Do not take any sleep remedies, including herbal medicines, without talking to a pharmacist or your specialist nurse first.
  • uncontrollable twitching, twisting or writhing movements (dyskinesias) – let your doctor or specialist nurse know as soon as possible

7. Pregnancy and breastfeeding

Co-careldopa is not generally recommended if you're pregnant or breastfeeding. This is because there's very little information about whether it's safe to use.

Speak to your doctor about the benefits and possible risks of taking co-careldopa. They will be able to help you decide on the best treatment for you and your baby.

8. Cautions with other medicines

There are some medicines that do not mix well with co-careldopa.

Tell your doctor, specialist nurse or a pharmacist if you're taking any of these medicines before you start taking co-careldopa:

  • iron supplements
  • tranylcypromine, phenelzine and isocarboxazid (for depression), or selegiline (for Parkinson's disease)
  • medicines for psychosis or schizophrenia, such as amisulpride, aripiprazole, haloperidol or risperidone
  • anti-sickness medicines, such as metoclopramide or prochlorperazine
  • medicines for high blood pressure (hypertension), such as atenolol, ramipril or amlodipine
  • medicines that make you sleepy, give you a dry mouth, or make it difficult to pee (called "anticholinergic" side effects), including antihistamines, antidepressants and medicines for an overactive bladder

Many medicines have these anticholinergic effects, so check with a pharmacist if you're not sure. They can affect how much co-careldopa your body takes in and stop it from working properly.

Taking painkillers

It's usually OK to take mild painkillers, such as ibuprofen and paracetamol, if you need pain relief.

Check with your doctor before taking any stronger prescription painkillers, including opioids (such as codeine, morphine or tramadol).

Mixing co-careldopa with herbal remedies and supplements

There's very little information about taking herbal remedies and supplements with co-careldopa. Not enough research has been done to know whether they can affect your medicine.


Tell your doctor or pharmacist if you're taking any other medicines, including herbal remedies, vitamins or supplements.

9. Common questions

Related conditions

Page last reviewed: 08/04/2020
Next review due: 08/04/2023