What the label lists and what reports show
Carbidopa and levodopa side effects
Carbidopa and levodopa's FDA label: “The most common adverse reactions reported with SINEMET have included dyskinesias, such as choreiform, dystonic, and other involuntary movements, and nausea.” FAERS holds 49,777 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is fall (4,736 reports).
- Generic listed
Check it at the source: the carbidopa and levodopa FDA label on DailyMed (effective August 1, 2026, Organon LLC); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of DUOPA?DUOPA may cause serious side effects, including: See “What is the most important information I should know about DUOPA?” Falling asleep during normal daily activities. DUOPA may cause you to fall asleep while you are doing daily activities such as driving, talking with other people, or eating. ○ You could fall asleep without any warning. ○ Some people using DUOPA have had car accidents because they fell asleep while driving. Do not drive or operate machinery until you are sure how DUOPA affects you. Tell your healthcare provider if you take other medicines that can make you sleepy such as sleep medicines, antidepressants, or antipsychotics. Low blood pressure when you sit or stand up quickly. After you have been sitting or lying down, stand up slowly until you know how DUOPA affects you. […]
Source: FDA drug label (Duopa), AbbVie Inc., effective March 19, 2026 (SPL set 7066d371-dc6a-0d6f-7bed-e5dd4ee912da), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsThe most common adverse reactions reported with SINEMET have included dyskinesias, such as choreiform, dystonic, and other involuntary movements, and nausea.
Table 3. Adverse Reactions in Study 1 for DUOPA in Patients with Advanced Parkinson’s disease
This table is printed in the Duopa label published by AbbVie Inc. of March 19, 2026; the label quoted above does not print one.
| Preferred Term | DUOPA (n = 37) % | Oral immediate-release carbidopa-levodopa a (n = 34) % |
|---|---|---|
| Complication of device insertion | 57 | 44 |
| Nausea | 30 | 21 |
| Constipation | 22 | 21 |
| Incision site erythema | 19 | 12 |
| Dyskinesia | 14 | 12 |
| Depression | 11 | 3 |
| Post procedural discharge | 11 | 9 |
| Peripheral edema | 8 | 0 |
| Hypertension | 8 | 0 |
| Upper respiratory tract infection | 8 | 0 |
| Oropharyngeal pain | 8 | 0 |
| Atelectasis | 8 | 0 |
| Confusional state | 8 | 3 |
| Anxiety | 8 | 3 |
| Dizziness | 8 | 6 |
| Hiatal hernia | 8 | 6 |
| Postoperative ileus | 5 | 0 |
| Sleep disorder | 5 | 0 |
| Pyrexia | 5 | 0 |
| Excessive granulation tissue | 5 | 0 |
| Rash | 5 | 0 |
| Bacteriuria | 5 | 0 |
| White blood cells urine positive | 5 | 0 |
| Hallucination | 5 | 3 |
| Psychotic disorder | 5 | 3 |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedThe most common adverse reactions reported with SINEMET have included dyskinesias, such as choreiform, dystonic, and other involuntary movements, and nausea. The following other adverse reactions have been reported with SINEMET: Body as a Whole Chest pain, asthenia. Cardiovascular Cardiac irregularities, hypotension, orthostatic effects including orthostatic hypotension, hypertension, syncope, phlebitis, palpitation. Gastrointestinal Dark saliva, gastrointestinal bleeding, development of duodenal ulcer, anorexia, vomiting, diarrhea, constipation, dyspepsia, dry mouth, taste alterations. Hematologic Agranulocytosis, hemolytic and non-hemolytic anemia, thrombocytopenia, leukopenia. Hypersensitivity Angioedema, urticaria, pruritus, Henoch-Schönlein purpura, bullous lesions (including pemphigus-like reactions). Musculoskeletal Back pain, shoulder pain, muscle cramps. Nervous System/Psychiatric Psychotic episodes including delusions, hallucinations, and paranoid ideation, bradykinetic episodes ("on-off" phenomenon), confusion, agitation, dizziness, somnolence, dream abnormalities including nightmares, insomnia, paresthesia, headache, depression with or without development of suicidal tendencies, dementia, pathological gambling, increased libido including hypersexuality, impulse control symptoms, seizures (including convulsions). Respiratory Dyspnea, upper respiratory infection. …
Source: FDA drug label, Organon LLC, effective August 1, 2026 (SPL set 9b17b028-964a-473c-823d-81423535bd66), via openFDA; the full label on DailyMed
What do FAERS reports show?
49,777 reports list carbidopa and levodopa among the medicines taken, each a report of something that happened, not proof the medicine caused it; 6,354 are coded as a death and 13,612 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 21 reactions below, 14 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Carbidopa and levodopa: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions