Sinemet
Combination product
Pronunciation: kar-bi-DOE-pa and lee-voe-DOE-pa
What it isDopamine precursor plus peripheral dopa-decarboxylase inhibitor; Parkinson disease motor symptoms.
Why this oneThe most effective symptomatic Parkinson drug; carbidopa cuts peripheral conversion, nausea and levodopa dose.
What limits itWithin 5–8 years most develop wearing-off, on-off swings and dyskinesia; gait, speech and cognition stop responding.
Pearls
- Dietary protein competes for absorption; separate doses from high-protein meals.
- Controlled-release tablets: do not split, crush or chew.
- Rytary ER capsules are not dose-interchangeable with other formulations.
- Advanced disease: enteral suspension infused 16 h/day via PEG-J.
(Carly and Levi) Dopey Cinema
Components (2)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Parkinson's disease, post-encephalitic parkinsonism, and symptomatic parkinsonism (carbon monoxide or manganese intoxication) | Adults | 1 tablet carbidopa/levodopa 25-100 TID (75 mg carbidopa/day) | Individualized; provide >=70–100 mg carbidopa/day | 8 tablets/day |
Titration Increase by 1 tablet every day or every other day as needed
Renal Use with caution; periodic renal function evaluation recommended during extended therapy
Hepatic Use with caution; periodic hepatic function evaluation recommended during extended therapy
Tablets of 1:4 (25-100) and 1:10 (10-100, 25-250) ratios may be combined to individualize dose; 25-250 no longer marketed by this manufacturer
Instructions
- Individualize by careful titration
- When transferring from levodopa alone, discontinue levodopa >=12 h before and start Sinemet at ~25% of the prior levodopa dose
- Do not abruptly reduce/discontinue (risk of hyperpyrexia, confusion, NMS-like syndrome)
- Evaluate vitamin B6 levels before and periodically during treatment; supplement if low
Available strengths
- tab 10/100, 25/100, 25/250 mg
- ER cap 23.75/95, 35/140, 36.25/145, 48.75/195, 52.5/210, 61.25/245, 70/280, 87.5/350 mg
- ER tab 25/100, 50/200 mg
- ODT 10/100, 25/100, 25/250 mg
- susp 4.63/20 mg/mL
Contraindications
- Concurrent use of nonselective MAO inhibitors (discontinue >=2 weeks before); MAO-B-selective inhibitors at recommended doses may be co-administered
- Narrow-angle glaucoma
Cautions
- Depression with suicidal tendencies
- Severe cardiovascular/pulmonary disease, asthma; arrhythmias post-MI
- Upper GI hemorrhage (history of peptic ulcer)
- Vitamin B6 deficiency and seizures
- Falling asleep during activities of daily living/somnolence
- Hallucinations/psychotic-like behavior
- Impulse control/compulsive behaviors
- Melanoma risk
Adverse reactions
- Dyskinesias (choreiform, dystonic, involuntary movements)
- Nausea
- Orthostatic hypotension
- Hallucinations/confusion
- Somnolence
Pregnancy No adequate human data; visceral and skeletal malformations seen in rabbits and reduced pup survival in rats; use only if benefit justifies risk.
Lactation Undefined
Cost
| Strength | #/mo | generic $/mo | CostPlus | |
|---|---|---|---|---|
| 10/100 mg | tab | 90 TID | $6.14 | offered |
| 25/100 mg | tab | 90 TID | $6.83 | offered |
| 25/250 mg | tab | 90 TID | $10.70 | offered |
Other forms: Carbidopa/ levodopa ER (RYTARY) · Carbidopa/ levodopa enteral (DUOPA)
Clinical profile
Part D rank #135.
Self-check
- What movement complication is listed with cumulative carbidopa–levodopa exposure?
Dyskinesia. - What response-pattern complication also accumulates?
Motor fluctuation.