Sinemet CR (Carbidopa/Levodopa)

Description

Sinemet CR (Carbidopa/Levodopa) is a medication commonly prescribed to help manage the symptoms of Parkinson's disease. Its active ingredients work together to boost levels of dopamine, a chemical in the brain that is lacking in people with Parkinson's disease. Sinemet CR is designed to release its ingredients slowly over time, which helps keep dopamine levels more stable. This medication can help with common symptoms of Parkinson's disease, such as shaking, stiffness, and slow movements.

Directions

Sinemet CR is taken by mouth, either with or without food, as directed by a doctor. The typical Sinemet CR dosage is often personalized based on a person’s health and how they respond to treatment. People typically start with a low dose to reduce the chance of side effects. The dosage may be gradually increased as needed. Most patients start with a tablet that has 25 mg of Carbidopa and 100 mg of Levodopa.

Avoid breaking, crushing, or chewing the sustained-release tablets because that can cause too much of the drug to be released at once, which can lead to more side effects. If a dose is missed, it should be taken as soon as possible unless it's almost time for the next dose; in that case, it’s better to skip the missed one to avoid taking too much.

Ingredients

The active ingredients in Sinemet CR are Carbidopa and Levodopa.

Contraindications

Avoid taking or using this medication if any of the following apply:

• Allergies to Carbidopa, Levodopa, or any ingredient of the formulation
• Use with nonselective monoamine oxidase (MAO) inhibitors or within 2 weeks of discontinuing such treatment
• Narrow-angle glaucoma, as the medication may worsen the condition

Cautions

• Before starting treatment with Sinemet CR, tell your healthcare provider if you have:
• Any existing health conditions
• Any allergies
• A list of all medications you are currently taking
• Whether you are pregnant or breastfeeding

• If you are switching from Levodopa alone to Sinemet CR, stop Levodopa at least 12 hours before starting Sinemet CR. Your doctor will adjust your dose to avoid side effects and ensure effective treatment. Always follow your doctor’s dosage instructions closely.
• Sinemet CR may cause dyskinesias (involuntary movements), which can happen at lower doses compared to Levodopa alone. If you experience new or worsening movements, inform your doctor right away, as your dosage may need adjustment. Additionally, some people may develop hallucinations, confusion, or psychotic-like behavior while taking Sinemet CR.
• Sinemet CR may cause extreme drowsiness or sudden sleep episodes during daily activities, like driving. If you experience these symptoms, avoid driving or operating machinery. Let your doctor know if you feel excessively sleepy or fall asleep unexpectedly.
• Sinemet CR may lead to depression, suicidal thoughts, or intense urges such as gambling, binge eating, or spending money. Report any unusual behaviors to your doctor, who may adjust or stop your medication if needed.
• Use Sinemet CR cautiously if you have heart, lung, liver, or kidney issues, or a history of peptic ulcers. Be mindful of sudden changes in diet, as high-protein foods can reduce the medication’s effectiveness. Your doctor may monitor your heart and other functions during treatment.
• People with Parkinson’s disease may have a higher risk of melanoma. Regular skin checks are important, so discuss this with your healthcare provider.
• Take Sinemet CR on a regular schedule without crushing or chewing the tablets. Dark-colored saliva, urine, or sweat may occur but is harmless, though it can stain clothing. If your symptoms worsen or you notice unusual changes, consult your doctor promptly.

Side Effects

The most common side effects of Sinemet CR reported in clinical trials include dyskinesia, nausea, and hallucinations. Patients also reported confusion, dizziness, and depression, with some experiencing urinary tract infections and headache. Other side effects such as vomiting, dry mouth, and back pain occurred in fewer than 2% of patients.

Uncommon side effects of this medication include feeling dizzy when standing up, seeing or hearing things that aren’t there, and having unusual dreams. There have also been reports of problems like dark-colored saliva or sweat, trouble controlling impulses, and serious mental health problems. In rare cases, severe reactions like swelling in the face or throat, heart problems, or bleeding in the stomach have been reported. If you notice any lasting or serious side effects, it’s important to reach out to your doctor.

References

1. Sinemet CR (Carbidopa/Levodopa) Product Monograph. Morgantown, WV: Mylan Pharmaceuticals, Inc.; 2014.
2. Sinemet CR (Carbidopa/Levodopa) Drug Label Information. Jersey City, NJ: Organon LLC; 2021.

About Dr. Gerardo Sison (Page Author)

An honors graduate of the University of Florida, Dr. Sison started his pharmacy career in a community setting, extending his services to hospitals and clinics over time. He has also worked in medication therapy management, advising patients on proper medication use for their chronic health conditions. Read More....