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Carbidopa oral

Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.





Carbidopa is used, together with another medication (levodopa), to treat the symptoms of Parkinson's disease (e.g., tremor). It works by allowing more levodopa to enter the brain so levodopa can work more effectively. It also helps to reduce some unwanted levodopa side effects (e.g. nausea). Carbidopa must be taken together with levodopa to be effective. Used alone, carbidopa has no effect on Parkinson's symptoms.

How To Use

Take this medication by mouth exactly as directed by your doctor. The dosage is based on your medical condition and response to therapy. If you are currently taking a levodopa-containing medicine, wait at least 12 hours after your last levodopa dose before starting this medication. Levodopa and carbidopa must always be taken at the same time. Your dosage of levodopa should also be reduced to account for the effects of this drug (only if you are currently taking levodopa by itself). Consult your doctor or pharmacist regarding your dosing schedule.

Side Effects

Side effects with carbidopa are rare and usually occur due to the effect of levodopa or other drugs used along with this medication. Consult the SIDE EFFECTS information of the levodopa-containing product(s), as well as any other drugs you are using. If you have any questions or notice any effects, consult your doctor or pharmacist. Abruptly stopping or reducing the dose of your levodopa may cause a rare syndrome (neuroleptic malignant syndrome-NMS) to occur. Tell your doctor immediately if any of these highly unlikely but serious side effects occur: fever, sweating, muscle stiffness, uncontrolled movements, confusion, fainting, unusually fast heartbeat, fast and shallow breathing, dizziness.


Tell your doctor your medical history, especially of: eye problems (e.g., narrow angle glaucoma), depression, other mental disorders (e.g., schizophrenia), heart or blood vessel problems (cardiovascular disease), kidney disease, liver disease, diabetes/thyroid/adrenal (endocrine) problems, ulcers, skin cancer (melanoma), severe lung disease (COPD), asthma, any allergies. This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor. It is not known whether this drug passes into breast milk. Because of the potential risk to the infant, breast-feeding while using this drug is not recommended. Consult your doctor before breast-feeding.

Drug Interactions

Tell your doctor of all prescription and nonprescription medication you may use, especially: all levodopa- containing products, medicine for blood pressure, "water pills" (diuretics such as furosemide or hydrochlorothiazide), antidepressants (e.g., tricyclics such as amitriptyline and nortriptyline), drugs for mental disorders (e.g., chlorpromazine, thioridazine, risperidone), metoclopramide, phenytoin, papaverine. Tell your doctor if you currently take, or have taken any MAO inhibitors (e.g., furazolidone, isocarboxazid, linezolid, moclobemide, phenelzine, procarbazine, selegiline, tranylcypromine) within the past 14 days. Consult your pharmacist. Carbidopa/levodopa-containing products may interfere with certain laboratory tests (e.g., LFT's, BUN, ketones). Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately.


Do not share this medication with others. Laboratory and/or medical tests may be performed to monitor your progress.

Missed Dose

If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.


Store at room temperature between 56 and 86 degrees F (15 and 30 degrees C) away from light and moisture.

Medical Alert

Your condition can cause complications in a medical emergency. For enrollment information call MedicAlert at 1-800-854-1166 (USA), or 1-800-668-1507 (Canada).