What the label lists and what reports show
Topiramate side effects
Topiramate's FDA label: “Most common (≥10% more frequent than placebo or low-dose topiramate) adverse reactions in adult and pediatric patients were: paresthesia, anorexia, weight loss, speech disorders/related speech problems, fatigue, dizziness, somnolence, nervousness, psychomotor …” FAERS holds 91,067 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 headache (6,530 reports).
- Generic listed
Check it at the source: the topiramate FDA label on DailyMed (effective June 1, 2026, Sun Pharmaceutical Industries, 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 topiramate tablet?Topiramate tablets may cause serious side effects including: See “What is the most important information I should know about topiramate tablets?” Effects on thinking and alertness. Topiramate tablets may affect how you think and cause confusion, problems with concentration, attention, memory, or speech. Topiramate tablets may cause depression or mood problems, tiredness, and sleepiness. Dizziness or loss of muscle coordination. Severe multiorgan reactions. Treatment with topiramate tablets may cause a serious allergic reaction that may affect your skin or other parts of your body such as your liver, kidneys, heart, or blood cells. This allergic reaction can be life-threatening and can cause death, particularly if it is not treated as early as possible. […]
Source: FDA drug label, Sun Pharmaceutical Industries, Inc., effective June 1, 2026 (SPL set 3c909a53-ae66-4b28-a741-b60bb25a69cf), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost common (≥10% more frequent than placebo or low-dose topiramate) adverse reactions in adult and pediatric patients were: paresthesia, anorexia, weight loss, speech disorders/related speech problems, fatigue, dizziness, somnolence, nervousness, psychomotor slowing, abnormal vision and fever (6.1) Migraine: Most common (≥5% more frequent than placebo) […]
A table the label prints in its adverse reactions section without a title; its column headings name the groups compared
| Body System/ Adverse Reaction | Placebo (N=101) % | Topiramate (N=98) % |
|---|---|---|
| Fatigue | 5 | 16 |
| Injury | 13 | 14 |
| Gait abnormal | 5 | 8 |
| Ataxia | 2 | 6 |
| Hyperkinesia | 4 | 5 |
| Dizziness | 2 | 4 |
| Speech disorders/Related speech problems | 2 | 4 |
| Nausea | 5 | 6 |
| Saliva increased | 4 | 6 |
| Constipation | 4 | 5 |
| Gastroenteritis | 2 | 3 |
| Weight loss | 1 | 9 |
| Purpura | 4 | 8 |
| Epistaxis | 1 | 4 |
| Somnolence | 16 | 26 |
| Anorexia | 15 | 24 |
| Nervousness | 7 | 14 |
| Personality disorder (behavior problems) | 9 | 11 |
| Difficulty with concentration/attention | 2 | 10 |
| Aggressive reaction | 4 | 9 |
| Insomnia | 7 | 8 |
| Difficulty with memory | 0 | 5 |
| Confusion | 3 | 4 |
| Psychomotor slowing | 2 | 3 |
| Infection viral | 3 | 7 |
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 in more detail in other sections of the labeling: Acute Myopia and Secondary Angle Closure Glaucoma [see Warnings and Precautions (5.1)] Visual Field Defects [see Warnings and Precautions (5.2)] Oligohidrosis and Hyperthermia [see Warnings and Precautions (5.3)] Metabolic Acidosis [see Warnings and Precautions (5.4)] Suicidal Behavior and Ideation [see Warnings and Precautions (5.5)] Cognitive/Neuropsychiatric Adverse Reactions [see Warnings and Precautions (5.6)] Decrease of Bone Mineral Density [see Warnings and Precautions (5.9)] Negative Effects on Growth (Height and Weight) [see Warnings and Precautions (5.10)] Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)/Multiorgan Hypersensitivity Reactions [ see Warnings and Precautions (5.11) ] Serious Skin Reactions [see Warnings and Precautions (5.12)] Anaphylaxis and Angioedema [see Warnings and Precautions (5.13)] Hyperammonemia and Encephalopathy (Without and With Concomitant Valproic Acid [VPA] Use) [see Warnings and Precautions (5.14)] Kidney Stones [see Warnings and Precautions (5.15)] Hypothermia with Concomitant Valproic Acid (VPA) Use [see Warnings and Precautions (5.16)] The data described in the following sections were obtained using topiramate tablets.
Source: FDA drug label, Sun Pharmaceutical Industries, Inc., effective June 1, 2026 (SPL set 3c909a53-ae66-4b28-a741-b60bb25a69cf), via openFDA; the full label on DailyMed
What do FAERS reports show?
91,067 reports list topiramate among the medicines taken, each a report of something that happened, not proof the medicine caused it; 6,839 are coded as a death and 23,609 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 19 reactions below, 13 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?
- Topiramate: 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