What the label lists and what reports show
Levodopa side effects
Levodopa's FDA label: “The most common adverse reactions (incidence ≥ 5% and higher than placebo) were cough, nausea, upper respiratory tract infection, and sputum discolored ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Merz Pharmaceuticals, LLC at 1-800-367-5109 or FDA …” FAERS holds 12,013 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 cough (2,270 reports).
- No generic listed
Check it at the source: the levodopa FDA label on DailyMed (effective July 20, 2026, Merz Pharmaceuticals, 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 INBRIJA?INBRIJA can cause serious side effects including: falling asleep during normal daily activities. INBRIJA may cause you to fall asleep while you are doing normal daily activities such as driving a car, doing physical tasks, using hazardous machinery, talking with other people, or eating. You could fall asleep without being drowsy or without warning. If you become drowsy while using INBRIJA, you should not drive or do activities where you need to be alert for your safety or the safety of others. Your chances of falling asleep while doing normal activities while using INBRIJA are greater if you take other medicines that cause drowsiness. Tell your healthcare provider if you take medicines that can make you sleepy such as sleep medicines, antidepressants, or antipsychotics. withdrawal-emergent hyperpyrexia and confusion. […]
Source: FDA drug label, Merz Pharmaceuticals, LLC, effective July 20, 2026 (SPL set 077c0f39-a3a2-4b2b-a184-09131889dcfb), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsThe most common adverse reactions (incidence ≥ 5% and higher than placebo) were cough, nausea, upper respiratory tract infection, and sputum discolored ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Merz Pharmaceuticals, LLC at 1-800-367-5109 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
Table 1: Adverse Reactions at an Incidence ≥2% and More Frequent with INBRIJA than with Placebo in Study 1
| Adverse Reactions | INBRIJA 84 mg N=114 % | Placebo N=112 % |
|---|---|---|
| Cough | 15 | 2 |
| Sputum discolored | 5 | 0 |
| Nasal discharge discoloration | 2 | 0 |
| Oropharyngeal pain | 2 | 0 |
| Nausea | 5 | 3 |
| Vomiting | 3 | 0 |
| Upper respiratory tract infection | 6 | 3 |
| Nasopharyngitis | 3 | 2 |
| Bronchitis/pneumonia | 2 | 0 |
| Dyskinesia | 4 | 1 |
| Headache | 2 | 0 |
| Fall | 3 | 2 |
| Laceration | 2 | 0 |
| Skin abrasion | 2 | 0 |
| Chest discomfort | 2 | 0 |
| Blood bilirubin increased | 2 | 0 |
| Red blood cell count decreased | 2 | 0 |
| Pain in extremity | 2 | 1 |
| Insomnia | 2 | 1 |
| Orthostatic hypotension/blood pressure decreased | 2 | 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 the labeling: Falling Asleep During Activities of Daily Living and Somnolence [see Warnings and Precautions (5.1) ] Withdrawal-Emergent Hyperpyrexia and Confusion [see Warnings and Precautions (5.2) ] Hallucinations/Psychosis [see Warnings and Precautions (5.3) ] Impulse Control/Compulsive Behaviors [see Warnings and Precautions (5.4) ] Dyskinesia [see Warnings and Precautions (5.5) ] Bronchospasm in Patients with Lung Disease [see Warnings and Precautions (5.6) ] Glaucoma [see Warnings and Precautions (5.7) ] The most common adverse reactions (incidence ≥ 5% and higher than placebo) were cough, nausea, upper respiratory tract infection, and sputum discolored ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Merz Pharmaceuticals, LLC at 1-800-367-5109 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. …
Source: FDA drug label, Merz Pharmaceuticals, LLC, effective July 20, 2026 (SPL set 077c0f39-a3a2-4b2b-a184-09131889dcfb), via openFDA; the full label on DailyMed
What do FAERS reports show?
12,013 reports list levodopa among the medicines taken, each a report of something that happened, not proof the medicine caused it; 1,359 are coded as a death and 2,717 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 2021 (2,286, against a median of 531 a year): FAERS counts follow reporting, which news, litigation and label changes can drive, not how often a reaction happens. Of the 19 reactions below, 6 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?
- 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