What the label lists and what reports show
Foscarbidopa and foslevodopa side effects
Foscarbidopa and foslevodopa's FDA label: “Most common adverse reactions for VYALEV (VYALEV incidence at least 10% and greater than oral carbidopa-levodopa incidence) were infusion/catheter site reactions, infusion/catheter site infections, hallucinations, and dyskinesia.” FAERS holds 7,378 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 on and off phenomenon (963 reports).
- No generic listed
Check it at the source: the foscarbidopa and foslevodopa FDA label on DailyMed (effective March 19, 2026, AbbVie Inc.); 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 VYALEV?See “What is the most important information I should know about VYALEV?” VYALEV can cause serious side effects including: Seeing things that are not there, hearing sounds or feeling sensations that are not real (hallucinations). This is a common and sometimes serious side effect. Hallucinations can happen in people who use VYALEV. Tell your healthcare provider if you have hallucinations. Unusual urges. Some people taking certain medicines to treat Parkinson’s disease, including VYALEV, have reported problems, such as gambling, compulsive eating, compulsive shopping, and increased sex drive. If you or your family members notice that you are having unusual urges or behaviors, talk to your healthcare provider. Infusion site reactions and infections. This is a common and sometimes serious side effect. Some people using VYALEV have had reactions and infections at the infusion site. […]
Source: FDA drug label, AbbVie Inc., effective March 19, 2026 (SPL set 28e806e4-951c-40a9-9f0c-d0929caf054c), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost common adverse reactions for VYALEV (VYALEV incidence at least 10% and greater than oral carbidopa-levodopa incidence) were infusion/catheter site reactions, infusion/catheter site infections, hallucinations, and dyskinesia.
Table 2. Adverse Reactions in Study 1 that Occurred in ≥3% of Patients with Advanced PD who Received VYALEV and 2% Difference from Active Control
| Adverse Reaction | VYALEV (n = 74 ) % | Oral immediate-release carbidopa-levodopa (n = 67 ) % |
|---|---|---|
| Infusion/catheter site reaction a | 62 | 8 |
| Infusion/catheter site infection b | 28 | 3 |
| Hallucination | 12 | 2 |
| Dyskinesia | 11 | 6 |
| On and off phenomenon | 8 | 0 |
| Balance disorder | 5 | 0 |
| Constipation | 5 | 0 |
| Peripheral swelling | 5 | 0 |
| Agitation | 4 | 2 |
| Insomnia | 4 | 2 |
| Psychotic disorder c | 4 | 2 |
| Dyspnea | 4 | 0 |
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 following serious adverse reactions are discussed below and elsewhere in labeling: Falling Asleep During Activities of Daily Living and Somnolence [see Warnings and Precautions ( 5.1 ) ] Hallucinations/Psychosis [see Warnings and Precautions ( 5.2 ) ] Impulse Control/Compulsive Behaviors [see Warnings and Precautions ( 5.3 ) ] Infusion Site Reactions and Infections [see Warnings and Precautions ( 5.4 )] Withdrawal-Emergent Hyperpyrexia and Confusion [see Warnings and Precautions ( 5.5 ) ] Dyskinesia [see Warnings and Precautions ( 5.6 ) ] Vitamin B6 Deficiency and Seizures [see Warnings and Precautions ( 5.7 ) ] Cardiovascular Ischemic Events [see Warnings and Precautions ( 5.8 ) ] Glaucoma [see Warnings and Precautions ( 5.9 )] Most common adverse reactions for VYALEV (VYALEV incidence at least 10% and greater than oral carbidopa-levodopa incidence) were infusion/catheter site reactions, infusion/catheter site infections, hallucinations, and dyskinesia. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact AbbVie Inc. at 1-800-633-9110 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. …
Source: FDA drug label, AbbVie Inc., effective March 19, 2026 (SPL set 28e806e4-951c-40a9-9f0c-d0929caf054c), via openFDA; the full label on DailyMed
What do FAERS reports show?
7,378 reports list foscarbidopa and foslevodopa among the medicines taken, each a report of something that happened, not proof the medicine caused it; 1,155 are coded as a death and 4,012 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. Reports rose sharply in 2025 (4,251, against a median of 0 a year): FAERS counts follow reporting, which news, litigation and label changes can drive, not how often a reaction happens. Of the 23 reactions below, 4 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?
- Foscarbidopa and foslevodopa: 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