Sinemet (Carbidopa/Levodopa) Dosage and Side Effects
SINEMET is used to treat the symptoms of Parkinson's disease. SINEMET is a combination of levodopa, the metabolic precursor of dopamine, and carbidopa, an aromatic amino acid decarboxylase inhibitor.
Proper Use of this medication
The dosage of SINEMET is variable and your physician will adjust it according to the severity of your disease and your response to treatment.
SINEMET is an immediate-release formulation of levodopa-carbidopa that is designed to begin release of ingredients within 30 minutes. For best results take SINEMET every day. It is important to carefully follow your physician's advice on how much SINEMET to take and how often to take it. Promptly inform your physician of any change in your condition such as nausea or abnormal movements, as this may require an adjustment in your prescription.
Do not change the dose regimen prescribed by your physician and do not add any additional antiparkinson medications, including other levodopa-carbidopa preparations, without first consulting your physician.
Do not stop taking this medicine abruptly or lower the dosage without checking with your physician. If you suddenly stop or reduce your dosage you may experience the following symptoms: stiff muscles, high temperature (fever) and mental changes.
In case of an overdose, contact your physician immediately so that medical attention may be given promptly.
For management of a suspected drug overdose, contact your regional Poison Control Centre.
Try to take SINEMET as prescribed. However, if you have missed a dose, take it as soon as you remember. If it is almost time to take your next tablet, do not take the missed tablet, but resume your normal schedule.
SINEMET is generally well tolerated. Like any other medicine, however, SINEMET may have unintended or undesirable effects, so called side-effects.
Very rare but serious side effects that have been reported include sudden sleep onset episodes.
Certain side effects that have been reported with SINEMET may affect some patients' ability to drive or operate machinery.
SINEMET can cause somnolence (excessive drowsiness) and sudden sleep onset episodes. Therefore you must refrain from driving or engaging in activities where impaired alertness may put yourself or others at risk of injury or death (e.g. operating machines) until such recurrent episodes and somnolence have resolved.
The most frequent side effects are: abnormal movements including twitching or spasms (which may or may not resemble your Parkinson's symptoms), and nausea.
Other possible side effects include: mental changes, dream abnormalities, hair loss, diarrhea, dizziness, vomiting, loss of appetite, and slow movement. Occasionally, dark colour (red, brown or black) may appear in your saliva, urine or sweat after you take SINEMET.
Warnings and Precautions
Serious Warnings and Precautions
Some people feel sleepy, drowsy, or, rarely, may suddenly fall asleep without warning (i.e. without feeling sleepy or drowsy) when taking SINEMET. During treatment with SINEMET take special care when you drive or operate a machine. If you experience excessive drowsiness or a sudden sleep onset episode, refrain from driving and operating machines, and contact your physician.
Studies of people with Parkinson's disease show that they may be at an increased risk of developing melanoma, a form of skin cancer, when compared to people without Parkinson's disease. It is not known if this problem is associated with Parkinson's disease or the drugs used to treat Parkinson's disease. Therefore, patients treated with SINEMET should have periodic skin examinations.
BEFORE taking SINEMET, tell your physician or pharmacist if you:
- have or have had any medical conditions including: allergies; depression or mental disturbances; lung, kidney, liver, heart or hormonal problems; skin cancer or suspicious skin lesions; ulcer in your gut (called “duodenal” or “peptic ulcer”); convulsions/seizures; or glaucoma
- have previously been treated with levodopa
- are pregnant or plan to become pregnant
- are breastfeeding or wish to breastfeed
- are going to have an operation that requires general anesthesia
- drive or operate machinery
Tell your doctor if you or your family member/caregiver notices you are developing urges to gamble, increased sexual urges, excessive eating or spending, and/or other intense urges that could harm yourself or others. These behaviors are called impulse control disorders. Your doctor may need to review your treatments.
It is not recommended to use SINEMET while you are pregnant or breast-feeding.
It is not known what effect SINEMET may have on human pregnancy. Levodopa, one of the components of SINEMET, is passed into human milk. If you are pregnant, may become pregnant or intend to breast-feed, tell your physician, who will help you weigh the benefits of the drug for you against possible risks to your baby.
As you improve on SINEMET, you may increase your physical activity gradually and with caution related to any other medical conditions you may have.
SINEMET should not be given to children under 18 years of age.
Interactions with this medication
Although SINEMET can generally be given with other medicines, there are exceptions. Tell your physician about all medicines you are taking or plan to take, including those obtained without a prescription.
It is particularly important to tell your physician if you are taking:
- antihypertensive drugs (used to treat elevated blood pressure)
- some medications used to treat psychiatric conditions or mental depression (including phenothiazines, butyrophenones, risperidone, selegiline, tricyclic antidepressants and monoamine oxidase inhibitors)
- tetrabenazine (medication used to treat conditions related to involuntary movements such as Huntingtons Disease)
- phenytoin (anti-epileptic medication)
- papaverine (medication for intestinal spasms)
- isoniazid (medication to treat tuberculosis)
- metoclopramide (for nausea and vomiting)
- iron salts (such as multivitamins tablets) which may reduce the amount of carbidopa and/or levodopa available to the body
A change in diet to foods that are high in protein (such as meat, fish, dairy products, seeds and nuts) may delay the absorption of levodopa and SINEMET may not work as well as it should.
Other related products
The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.