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Active substance(s): CARBIDOPA / LEVODOPA

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(carbidopa / levodopa)
This medicine is available as the above name but will be referred to as Sinemet CR throughout the following leaflet.
Please note that the leaflet also contains information about Half Sinemet® CR 25mg/100mg Prolonged-Release
Read all of this leaflet carefully before you start taking this medicine.

Keep this leaflet. You may need to read it again.

If you have any further questions, ask your doctor or pharmacist.

This medicine has been prescribed for you. Do not pass it on to others. It may harm them, even if their
symptoms are the same as yours.

If any of the side effects get serious, or if you notice any side effects not listed in this leaflet, please tell your
doctor or pharmacist.
In this leaflet:
1. What Sinemet CR is and what it is used for
2. Before you take Sinemet CR
3. How to take Sinemet CR
4. Possible side effects
5. How to store Sinemet CR
6. Further information
Sinemet CR improves the signs of Parkinson’s disease. Parkinson’s disease is a long-term illness where:
• you become slow and unsteady
• your muscles feel stiff
• you may develop shaking or trembling (called ‘tremor’).
If not treated, Parkinson’s disease can make it hard for you to continue your normal daily activities.
Sinemet CR contains two different medicines called: levodopa and carbidopa.
• levodopa turns into a material called ‘dopamine’ in your brain. The dopamine helps to improve the signs of your
Parkinson’s disease.
• carbidopa belongs to a group of medicines called ‘aromatic amino acid decarboxylase inhibitors’. It helps
levodopa work more effectively by slowing the speed at which levodopa is broken down in your body.
Do not take Sinemet CR if:
• you are allergic (hypersensitive) to carbidopa or levodopa or any of the other ingredients of Sinemet CR (listed
in Section 6)
• you have ever had skin cancer or you have any unusual moles which have not been examined by your doctor
• you are taking certain medicines called ‘MAOIs’ (Monoamine Oxidase Inhibitors) used for depression. You need
to stop using these medicines at least two weeks before you start Sinemet CR (see also under ‘Taking other
medicines’ below)
• you have a condition called ‘narrow-angle glaucoma’ that may cause a sudden build up of pressure in the eye
• you have a severe mental disorder
• you are pregnant, might become pregnant, or are breast-feeding.
Do not take Sinemet CR if any of the above apply to you. If you are not sure, talk to your doctor or pharmacist
before taking Sinemet CR.
Take special care with Sinemet CR
Check with your doctor or pharmacist before taking your medicine if:
• you have a history of fits (convulsions)
• you have had an ulcer in your gut (called ‘duodenal’ or ‘peptic ulcer’) or have vomited blood
• you have had a heart attack, heart beat problems, circulation or breathing problems
• you have had kidney, liver or hormonal problems
• you have had depression or other mental problems
• you have a condition called ‘chronic wide-angle glaucoma’ that may cause a build up of pressure in the eye.
You will need to have regular checks on the pressure in your eye
• you sometimes have sudden sleep attacks or sometimes feel very sleepy
• you are due to have surgery.
If you are not sure if any of the above apply to you, talk to your doctor or pharmacist before taking Sinemet CR.
Tell your doctor if you or your family/carer notices you are developing addiction-like symptoms leading to craving
for large doses of Sinemet CR and other medicines used to treat Parkinson’s disease.
Tell your doctor if you or your family/carer notices you are developing urges or cravings to behave in ways that are
unusual for you or you cannot resist the impulse, drive or temptation to carry out certain activities that could harm
yourself or others. These behaviours are called impulse control disorders and can include addictive gambling,
excessive eating or spending, an abnormally high sex drive or an increase in sexual thoughts or feelings. Your
doctor may need to review your treatments.
Taking other medicines
Please tell your doctor or pharmacist if you are taking or have recently taken any other medicines, including
medicines obtained without a prescription. This includes herbal medicines. This is because Sinemet CR can affect
the way some other medicines work. Also some other medicines can affect the way Sinemet CR works.
In particular tell your doctor or pharmacist if you are taking any of the following medicines:
• Medicines for Parkinson’s disease containing levodopa:
- If they are ‘slow release’, you will need to wait 24 hours after your last dose before starting Sinemet CR.
- If they are ‘normal release’, you will need to wait 12 hours after your last dose before starting Sinemet CR.
- Tell the doctor or pharmacist even if you have only taken them in the past.
Medicines for Parkinson’s disease which do not contain levodopa will usually be continued. However, your dose
may be changed.
• Medicines for mental problems (including depression), tuberculosis (TB), high blood pressure, muscle spasms,
epilepsy or other diseases related to involuntary movements. Your dose may need to be changed.
• Medicines to treat low iron. Your dose may need to be changed.
• Medicines called ‘MAOIs’ (see also ‘Do not take Sinemet CR if’).
• Anticholinergic medicines (such as orphenadrine, trihexyphenidyl, benzatropine and procyclidine). Your dose
may need to be changed.
• Phenytoin which is used to treat fits (convulsions).
• Papaverine which is used to treat impotence in men.
If you are not sure if any of the above apply to you, talk to your doctor or pharmacist before taking this medicine.
Your doctor or pharmacist has a more complete list of medicines to avoid while taking Sinemet CR.
Tests while you are taking Sinemet CR
This medication can affect some laboratory tests that your doctor may perform on blood or urine samples. Please
remind your doctor if you are taking Sinemet CR and are having any tests.
Taking Sinemet CR with food and drink
Try to avoid taking your tablets with a heavy meal. If your diet contains too much protein (meat, eggs, milk, cheese)
Sinemet CR may not work as well as it should.
Pregnancy and breast-feeding
Do not take Sinemet CR if you are pregnant, might become pregnant or are breast-feeding. Levodopa, one of the
substances in Sinemet CR, is passed into human milk.
Ask your doctor or pharmacist for advice before taking any medicine, if you are pregnant or breast-feeding.
Driving and using machines
• Sinemet CR affects different people in different ways. Some people have side effects which affect their ability to
drive or use tools or machines. (see Section 4 Possible side effects). Do not drive or use tools or machines if
you get these effects.
• Sinemet CR can also make you sleepy or cause ‘sudden sleep attacks’. If this happens to you, you must not
drive or use tools or machines. Your doctor will tell you if you can start driving again if these attacks stop.
Always take Sinemet CR exactly as your doctor has told you. You should check with your doctor or pharmacist if
you are not sure.
Taking this medicine
• Take this medicine by mouth. You must swallow your tablets whole. Do not break, crush or chew the tablets.
• Although your medicine can have an effect after one day, it may take up to seven days to work.
• Take them at regular time intervals according to your doctor’s instructions.
• Do not change the times at which you take your tablets or take any other medicines for Parkinson’s disease
without first consulting your doctor. You should not take Sinemet CR or Half Sinemet CR tablets at intervals of
less than 4 hours apart.
• Try to avoid taking your tablets with a heavy meal.
If you have not had levodopa before
The usual starting dose for Sinemet CR is one tablet twice a day.
If you have had levodopa before
• your doctor will ask you to stop taking your medicine for Parkinson’s disease for 8 hours before you start taking
Sinemet CR.
The usual starting dose for Sinemet CR is one tablet twice a day. Your doctor may ask you to take Half Sinemet
CR to help in determining the correct dose.
A combination of more than one Sinemet or Sinemet CR product may be prescribed by your doctor. If you have
been given different Sinemet or Sinemet CR tablets to take make sure that you are taking the correct one at the
right time. Remember: Half Sinemet CR is a lower dose tablet than Sinemet CR.

Children under 18 years of age
Sinemet CR is not suitable for children under the age of 18 years.
If you take more Sinemet CR than you should
If you take too many tablets see your doctor immediately.
If you forget to take Sinemet CR
Do not take a double dose to make up for a forgotten dose.
If you stop taking Sinemet CR
Do not stop taking Sinemet CR or change your dose without talking to your doctor first. When you stop taking
Sinemet CR the following can occur: stiff muscles, high temperature (fever) and mental changes.
If you have any further questions on the use of this product, ask your doctor or pharmacist.
Like all medicines, Sinemet CR can cause side effects, although not everybody gets them.
Stop taking Sinemet CR and see your doctor straight away, if you notice any of the following side effects:
• allergic reaction, the signs may include hives (nettle rash), itching, rash, swelling of your face, lips, tongue or
throat. This may cause difficulty in breathing or swallowing
• chest pain
• uneven (irregular) heart beat or palpitations
• dizziness on standing-up quickly
• bleeding from your gut which may be seen as blood in your faeces or darkened faeces (gastro-intestinal
• blood problems, the signs may include pale skin (pallor), tiredness, fever, sore throat or mild bruising and
prolonged bleeding after injury
• stiff muscles, high fever
• mental changes including delusions, hallucinations and depression
• fits (convulsions).
The most common side effects are
• abnormal movements such as twitching or spasms (which may or may not be like your Parkinson’s symptoms)
• nausea.
Other side effects include
• fainting, anorexia, high blood pressure
• inflammation of the veins, being sick (vomiting), diarrhoea, discoloration of urine, sweat or saliva
• on-off phenomenon, characteristic of some people with long-standing Parkinson’s disease. This is when you
can have unpredictable changes from being mobile - “on” - to a sudden inability to move - “off”. “Off” to “on” can
occur just as suddenly
• dizziness; sleepiness (including excessive drowsiness or sudden sleep onset episodes), pins and needles
• dream abnormalities, confusion, feeling agitated, shortness of breath, hair loss.
You may experience the following side effects:
• Craving for large doses of Sinemet CR in excess of that required to control motor symptoms, known as
dopamine dysregulation syndrome. Some patients experience severe abnormal involuntary movements
(dyskinesias), mood swings or other side effects after taking large doses of Sinemet CR.
• inability to resist the impulse to perform an action that could be harmful, which may include:
o strong impulse to gamble excessively despite serious personal or family consequences
o altered or increased sexual interest and behaviour of significant concern to you or to others, for example, an
increased sexual drive
o uncontrollable excessive shopping or spending
o binge eating (eating large amounts of food in a short time period) or compulsive eating (eating more food
than normal and more than is needed to satisfy your hunger)
Tell your doctor if you experience any of these behaviours; he/she will discuss ways of managing or
reducing the symptoms.
Side effects that have been reported with medicines containing levodopa.
These may be experienced when taking Sinemet CR.
Nervous system:
• loss of control over the voluntary movements of everyday life
• numbness, increased hand tremor, muscle twitching, muscle cramp, irregular movement of jaw muscles
resulting in difficulty opening the mouth
• difficulty sleeping, feeling anxious or high, falling over and abnormal walking patterns
• headache
• drooping eyelid and dilated pupil
• changes in vision, irregular movement of the eye
Digestive system:
• indigestion, dry mouth, bitter taste
• swelling of the salivary glands, difficulty swallowing, grinding of the teeth
• hiccups, abdominal pain and distress, constipation, wind
• burning sensation of the tongue
• persistent abnormal erection of the penis
• difficulty passing urine or incontinence (inability to control urine flow)
• changed patches of pigmented skin, including, irritated or irregular moles, or moles in which you have noticed
changes (melanoma)
• weight gain or loss, swelling in the limbs
• flushing, hot flushes, increased sweating
• feeling weak, faint or tired
• hoarseness, general feeling of being unwell
• increased energy or activity, unusual breathing pattern
If any symptoms persist or you experience any other side effects please tell your doctor or pharmacist. It will help if
you make a note of what you experienced, when it started and how long it lasted.
Reporting of side effects
If you get any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this
leaflet. You can also report side effects directly via the Yellow Card Scheme at: or
search for MHRA Yellow Card in the Google Play or Apple App Store. By reporting side effects, you can help
provide more information on the safety of this medicine.

Keep out of the sight and reach of children
Do not store above 30°C. Store in the original package.
Do not use any tablets after the expiry date which is stated on the bottle and carton. The expiry date refers to
the last day of that month.
• If the tablets become discoloured or show any other signs of deterioration, you should seek the advice of your
pharmacist who will tell you what to do.
• Medicines should not be disposed of via wastewater or household waste. Ask your pharmacist how to dispose
of medicines no longer required. These measures will help to protect the environment.

What Sinemet CR contains
• Each tablet contains carbidopa equivalent to 50mg of anhydrous carbidopa and 200mg levodopa.
• The other ingredients are hydroxypropylcellulose, magnesium stearate, hypromellose, indigo carmine (E132)
and allura red AC (E129).
What Sinemet CR looks like and contents of the pack
Sinemet CR is dappled purple coloured, oval shaped, bi-convex tablets scored "521" on one side and plain on the
reverse available in HDPE bottle containing 100 tablets.
PLPI 15814/1023
Sinemet CR is manufactured by Merck Sharp & Dohme B.V., Waarderweg 39, The Netherlands. Procured from
within the EU and repackaged by the Product Licence holder: O.P.D. Laboratories Ltd., Unit 6 Colonial Way,
Watford, Herts WD24 4PR.
Leaflet revision and issue date (Ref.): 18.12.2017.
Sinemet is a registered Trade Mark of Merck Sharp & Dohme Corp., USA.

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.