Can topiramate (antiepileptic medication) cause numbness?

Topiramate and Numbness

Yes, topiramate commonly causes numbness and tingling sensations (paresthesias), particularly in the arms and legs, occurring in 4-23% of patients—making it one of the most frequent side effects of this medication. 1

Mechanism and Characteristics

Paresthesias associated with topiramate are directly related to its carbonic anhydrase inhibitor properties. 2 This side effect:

• Typically manifests as tingling sensations in the extremities 2
• Occurs more frequently in monotherapy epilepsy trials compared to adjunctive therapy trials 2
• Usually appears early in treatment but rarely leads to discontinuation 2
• Is dose-related and can be influenced by the rate of dose titration 3

Clinical Significance and Management

In the majority of cases, paresthesia does not require treatment discontinuation. 2 The FDA drug label explicitly identifies "tingling of the arms and legs (paresthesia)" as a common side effect that patients should expect. 2

Frequency Across Different Populations

The incidence varies by indication and dosing:

• In adult monotherapy epilepsy trials: paresthesia was among the most common adverse events at 400 mg/day 2
• In pediatric monotherapy trials (ages 10-16): paresthesia occurred in 18% of patients on 400 mg/day versus 7% on 50 mg/day 2
• Overall reported range: 4-23% of all patients treated with topiramate 1

Comparison to Other Side Effects

While paresthesias are very common, they are generally less troublesome than cognitive side effects. Cognitive problems occur less frequently than paresthesia but are more likely to cause treatment discontinuation. 4 Other common side effects that may prompt discontinuation include:

• Memory difficulties 5
• Severe headaches 5
• Acute narrow-angle glaucoma 5
• Emergent suicidal ideation 5

Clinical Counseling Points

Patients should be informed before starting topiramate that tingling sensations in the extremities are a common, expected side effect that typically does not require stopping the medication. 2 This proactive counseling can prevent unnecessary anxiety and improve medication adherence.

The paresthesias are pharmacologically predictable given topiramate's mechanism as a carbonic anhydrase inhibitor—the same class effect seen with acetazolamide and dichlorphenamide. 2