carbidopa/levodopa vs risperidone

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Side-by-side comparison of carbidopa/levodopa and risperidone. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

minor Known Drug Interaction

7.5 Dopamine D2 Receptor Antagonists Dopamine D2 receptor antagonists (e.g., metoclopramide, phenothiazines, butyrophenones, risperidone) may reduce the therapeutic effects of levodopa.

Drug Class
carbidopa/levodopa Dopamine Precursor Combination
risperidone Atypical Antipsychotic
Type
carbidopa/levodopa Prescription
risperidone Prescription
Summary
carbidopa/levodopa

This medicine contains carbidopa, levodopa, and entacapone. It is used to treat Parkinson's disease.

risperidone

Risperidone is a medicine used to treat certain mental disorders. It can help reduce symptoms like hallucinations, delusions, and aggression.

What It Treats
carbidopa/levodopa

This medicine treats Parkinson's disease. It can help when other medicines stop working as well near the end of a dose. It can also replace other medicines containing similar ingredients.

risperidone

Risperidone is used to treat schizophrenia in adults and teens. It also treats manic or mixed episodes of bipolar I disorder, either alone or with lithium or valproate. Additionally, it can help with irritability, including aggression and self-injury, in children and teens with autism.

How It Works
carbidopa/levodopa

Levodopa turns into dopamine in your brain, helping to control movement. Carbidopa helps levodopa get to your brain. Entacapone helps levodopa work longer.

risperidone

Risperidone works by changing the levels of certain natural substances in the brain. These substances are called neurotransmitters. By balancing these chemicals, risperidone can reduce symptoms of mental disorders.

Common Side Effects
carbidopa/levodopa
  • Uncontrolled movements
  • Diarrhea
  • Nausea
  • Belly pain
  • Vomiting
risperidone
  • Parkinsonism (slowed movement, stiffness)
  • Restlessness
  • Muscle stiffness or spasms
  • Tremors
  • Sleepiness
FAERS Reports
carbidopa/levodopa
  • Fall 4,293
  • Seeing or hearing things that are not there 3,733
  • Shaking 3,257
  • Uncontrolled movements 2,903
  • Death 2,727
risperidone
  • Gynaecomastia 24,608
  • Abnormal Weight Gain 9,446
  • Weight Increased 9,088
  • Emotional Disorder 5,947
  • Injury 4,623
Serious Warnings
carbidopa/levodopa

This medicine can make you fall asleep suddenly, even when you feel awake. Be careful when driving or doing other activities where you need to be alert. Stopping this medicine suddenly can cause serious problems like fever and confusion.

risperidone

Risperidone may increase the risk of death in elderly patients who have dementia-related psychosis. Risperidone is not approved for treating dementia-related psychosis.

Pregnancy
carbidopa/levodopa

This medicine may harm your unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. It is not known if this medicine passes into breast milk.

risperidone

Tell your doctor if you are pregnant or plan to become pregnant. Babies born to mothers who take risperidone in the last 3 months of pregnancy may have withdrawal symptoms or other problems after birth. There is a pregnancy registry to monitor outcomes in women exposed to risperidone during pregnancy. You can contact the registry at 1-866-961-2388.

Also Compare, Nearby Drugs

How to Read This carbidopa/levodopa vs risperidone Comparison

carbidopa/levodopa is classified in the Dopamine Precursor Combination drug class, while risperidone sits within the Atypical Antipsychotic class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, carbidopa/levodopa has 16,913 submissions while risperidone has 53,712. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known minor interaction flagged in FDA labeling, attributed to risperidone blocks the brain receptors that levodopa needs to work, which can stop your parkinson's medicine from helping you.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for carbidopa/levodopa or risperidone.

Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.