Information update

Information Update - Epilepsy drug Zarontin: Defective softgel capsules may reduce drug's effectiveness

Starting date:
September 22, 2016
Posting date:
September 22, 2016
Type of communication:
Information Update
Source of recall:
Health Canada
Important Safety Information
General Public
Identification number:


Erfa Canada 2012 Inc. and Health Canada have received reports of defective 250 mg Zarontin softgel capsules (DIN 00022799), a prescription epilepsy drug, including reports of patients experiencing a higher frequency of  seizures after taking capsules that appeared cloudy, broken, leaking, sticky or clumping together. Zarontin is available as capsules or as a syrup. The syrup is not affected by this issue.

Zarontin is used to control absence - or petit mal - seizures. Such seizures last a few seconds and are noticeable by a blank or absent state. They are more common in children than adults.

The softgel capsules may be particularly susceptible to deterioration from temperature or humidity changes. Exposure to high humidity levels during, for example, storage, transportation or handling, can cause the capsules to swell or become sticky, and break or leak. Pulling apart capsules that have become stuck together can increase the chance of tears and leaks.

Defective capsules - such as those that are cracked or leaking - can lead to a loss of medicinal ingredient, reducing the effectiveness of the medication. This could potentially lead to a reappearance or an increase in the number of absence seizures among patients.

Given that not all capsules are defective, and to avoid a shortage of this medically necessary drug, Zarontin capsules are not being recalled at this time. Health Canada will continue to work with the company, Erfa Canada 2012 Inc., on this issue and will advise Canadians of new safety information as required. A communication is being distributed to advise pharmacists on this issue.

What you should do

  • Check Zarontin capsules before taking them or giving them to a child. Do not consume them if they look unusual (e.g., dull, cloudy, sticky, coated with film, broken, cracked, leaking, or clumping together).
  • Only bottles containing defective capsules should be returned to your pharmacy for replacement.
  • Do not stop taking this medication unless advised to do so by your healthcare provider, as suddenly stopping treatment could worsen the condition.
  • Store Zarontin capsules in a dry place at room temperature (15°C-25°C). Never store them in your bathroom or other areas prone to humidity and temperature changes. Protect them from light and freezing.

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