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Carbidopa and levodopa

Brand names: Sinemet, Rytary, Dhivy, Duopa

Carbidopa-levodopa is the most effective medicine for Parkinson's symptoms like slowness, stiffness, and tremor.

Brand namesSinemet, Rytary, Dhivy, Duopa
Type of medicineParkinson's medicine
Prescription?Prescription
ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.

Overview

Levodopa turns into dopamine in the brain; carbidopa helps more of it get there and lowers nausea.

What it's used for

  • Parkinson's disease
  • Parkinson-like symptoms from other causes

How to take it

  • Take it on a regular schedule. High-protein meals can block absorption; ask about timing doses around meals.
  • Swallow extended-release tablets whole.
  • Don't stop suddenly; it can cause high fever and severe stiffness.

Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.

Side effects

Common side effects

  • Nausea
  • Dizziness when standing
  • Uncontrolled movements (dyskinesia)
  • Sleepiness
  • Dark urine or sweat (harmless)
Call 911High fever, stiff muscles, and confusion, especially after stopping or lowering the dose
Call 911Falling asleep suddenly during activities like driving
Call your provider todaySeeing or hearing things, or new confusion
Call your provider todayStrong urges you can't control, like gambling or shopping
Call your provider todayBlack or bloody stools

Warnings

  • Have your skin checked; Parkinson's raises melanoma risk.
  • Effects may wear off before the next dose ('wearing off'); tell your provider.

Other medicines, foods, and alcohol

  • Never take within 14 days of a nonselective MAOI.
  • Iron supplements lower absorption.
  • Antipsychotics and metoclopramide work against it.

Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.

Pregnancy and breastfeeding

Talk with your provider.

Missed doses, overdose, and storage

If you miss a dose

Take it as soon as you remember, unless it's almost time for your next dose. Then skip the missed dose. Don't take two doses at once.

If someone takes too much

Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.

Storing it

Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.

Conditions it's used for

Sources

Last updated 2026-11-13.