Levodopa + Carbidopa (CR tablet)

Generic Details

Generic Name

Levodopa-Carbidopa-CR Tablet

Other Names

  • Sinemet CR
  • Duopa

Drug Class

  • Antiparkinsonian

Chemical Formula

Molecular Weight

Mechanism of Action

  • Levodopa is a dopamine precursor converted to dopamine in the brain. Carbidopa inhibits the peripheral breakdown of levodopa, increasing its availability in the brain.

Indications

  • Parkinson's Disease

Common Dosage Forms

  • Extended-Release Tablet

Typical Dosage

  • One tablet 2-3 times daily

Pediatric Dosage

  • Not established

Geriatric Dosage

  • May require lower doses

Side Effects

  • Nausea
  • Vomiting
  • Dizziness
  • Dyskinesia
  • Orthostatic Hypotension

Contraindications

  • Narrow-angle glaucoma
  • Use of nonselective monoamine oxidase inhibitors (MAOIs)

Pregnancy Category

  • C - Risk cannot be ruled out

Lactation Safety

  • Compatible with breastfeeding under healthcare provider supervision

Drug Interactions

  • MAOIs
  • Antipsychotics
  • Metoclopramide

Overdose Symptoms

  • Dyskinesias
  • Hallucinations
  • Hypotension
  • Arrhythmias

Antidote for Overdose

  • Symptomatic and supportive treatment

Storage Conditions

  • Store in a cool, dry place away from light and moisture

Pharmacokinetics

  • Absorption: Varies
  • Distribution: Crosses the blood-brain barrier
  • Metabolism: Levodopa - liver; Carbidopa - intestines
  • Excretion: Primarily urine

Precautions

  • Monitor for dyskinesias
  • Avoid sudden withdrawal
  • Caution in patients with history of psychosis or cardiovascular disease

Warnings

  • May cause or exacerbate psychiatric symptoms
  • May cause orthostatic hypotension

Others