Zonisamide: Side Effects, Uses & Monitoring
Zonisamide capsules USP are indicated as adjunctive therapy in the treatment of partial seizures in adults with epilepsy.
- Data source
- FDA labeling via NIH DailyMed (label b20a51ef…)
- Label version
- current
- Last reviewed
- 2026
Reported adverse reactions
Reactions listed in current FDA labeling, with the highest frequency reported across summarized placebo-controlled trials.
| Adverse reaction (as reported in labeling) | Reported frequency* |
|---|---|
| Somnolence | 17% |
| Anorexia | 13% |
| Dizziness | 13% |
| Headache | 10% |
| Nausea | 9% |
| Agitation/irritability | 9% |
| Fatigue | 8% |
| Tiredness | 7% |
| Abdominal pain | 6% |
| Ataxia | 6% |
| Confusion | 6% |
| Difficulty concentrating | 6% |
| Difficulty with memory | 6% |
| Depression | 6% |
| Insomnia | 6% |
| Diplopia | 6% |
| Diarrhea | 5% |
| Speech abnormalities | 5% |
| Flu syndrome | 4% |
| Nystagmus | 4% |
*Highest percentage reported for the active moiety across placebo-controlled trial tables in current FDA labeling. Values reflect trial reporting, not your individual risk.
Labeled uses (from FDA prescribing information)
Zonisamide capsules USP are indicated as adjunctive therapy in the treatment of partial seizures in adults with epilepsy.
Conditions associated with Zonisamide in labeling
Frequently Asked Questions
What is Zonisamide used for?
FDA labeling lists the approved uses shown above under "Labeled uses." This summary is informational; only a qualified prescriber can determine whether a medication is appropriate for you.
What are the most commonly reported side effects of Zonisamide?
The table above shows adverse reactions and the highest frequencies reported in placebo-controlled trials summarized in current FDA labeling for Zonisamide. Individual risk varies.
Does Zonisamide require lab monitoring?
Monitoring needs vary. Ask your healthcare provider whether any lab tests apply while taking Zonisamide.
Where does this information come from?
All clinical facts on this page were extracted from the current FDA-registered product labeling for this ingredient, published by manufacturers through NIH DailyMed. See the source link below.
Medical disclaimer: Educational content extracted from public FDA labeling. Not medical advice. Always consult a qualified healthcare professional before starting, stopping, or changing any medication.