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Zonisamide FDA Alerts

The FDA Alerts below may be specifically about zonisamide or relate to a group or class of drugs which include zonisamide.

MedWatch Safety Alerts are distributed by the FDA and published by Drugs.com. Following is a list of possible medication recalls, market withdrawals, alerts and warnings.

Recent FDA Alerts for zonisamide

Antiepileptic Drugs

[UPDATE 05/05/2009] FDA notified healthcare professionals that it approved updated labeling for antiepileptic drugs used to treat epilepsy, psychiatric disorders, and other conditions (e.g., migraine and neuropathic pain syndromes). FDA also required development of a medication guide, to be issued to patients each time the product is dispensed. Since issuing safety alerts on December 16, 2008 and January 31, 2008, FDA has been working with the manufacturers of drugs in this class to better understand the suicidality risk. Eleven antiepileptic drugs were included in a pooled analysis of placebo-controlled clinical studies in which these drugs were used to treat epilepsy as well as psychiatric disorders and other conditions. The increased risk of suicidal thoughts or behavior was generally consistent among the eleven drugs, with varying mechanisms of action and across a range of indications. This observation suggests that the risk applies to all antiepileptic drugs used for any indication.

[UPDATE 12/16/2008] The FDA has completed its analysis of reports of suicidality (suicidal behavior or ideation [thoughts]) from placebo-controlled clinical trials of drugs used to treat epilepsy, psychiatric disorders, and other conditions. Based on the outcome of this review, FDA is requiring that all manufacturers of drugs in this class include a Warning in their labeling and develop a Medication Guide to be provided to patients prescribed these drugs to inform them of the risks of suicidal thoughts or actions.

[Posted 01/31/2008] FDA informed healthcare professionals that the Agency has analyzed reports of suicidality (suicidal behavior or ideation) from placebo-controlled clinical studies of eleven drugs used to treat epilepsy as well as psychiatric disorders, and other conditions. In the FDA's analysis, patients receiving antiepileptic drugs had approximately twice the risk of suicidal behavior or ideation (0.43%) compared to patients receiving placebo (0.22%). The increased risk of suicidal behavior and suicidal ideation was observed as early as one week after starting the antiepileptic drug and continued through 24 weeks. The results were generally consistent among the eleven drugs. The relative risk for suicidality was higher in patients with epilepsy compared to patients who were given one of the drugs in the class for psychiatric or other conditions.

Healthcare professionals should closely monitor all patients currently taking or starting any antiepileptic drug for notable changes in behavior that could indicate the emergence or worsening of suicidal thoughts or behavior or depression.

The drugs included in the analyses include (some of these drugs are also available in generic form):

Carbamazepine (marketed as Carbatrol, Equetro, Tegretol, Tegretol XR)
Felbamate (marketed as Felbatol)
Gabapentin (marketed as Neurontin)
Lamotrigine (marketed as Lamictal)
Levetiracetam (marketed as Keppra)
Oxcarbazepine (marketed as Trileptal)
Pregabalin (marketed as Lyrica)
Tiagabine (marketed as Gabitril)
Topiramate (marketed as Topamax)
Valproate (marketed as Depakote, Depakote ER, Depakene, Depacon)
Zonisamide (marketed as Zonegran)

Although the 11 drugs listed above were the ones included in the analysis, FDA expects that the increased risk of suicidality is shared by all antiepileptic drugs and anticipates that the class labeling changes will be applied broadly.

[December 16, 2008; UPDATED May 05, 2009 - Drug Information Page - FDA]
[January 31, 2008 - Healthcare Professional Information Sheet - FDA]


Zonisamide (marketed as Zonegran, and generics)

[Posted 02/23/2009] FDA notified healthcare professionals that updated clinical data has determined that treatment with zonisamide, indicated as adjunctive therapy in the treatment of partial seizures in adults with epilepsy, can cause metabolic acidosis in some patients. Patients with predisposing conditions or therapies may be at greater risk for developing metabolic acidosis and the risk of zonisamide-induced metabolic acidosis appears to be more frequent and severe in younger patients. FDA recommends that healthcare professionals measure serum bicarbonate before starting treatment and periodically during treatment with zonisamide, even in the absence of symptoms and is working with the makers of zonisamide to revise the product labeling to reflect this new safety information. The notification includes recommendations for healthcare providers, information for patients, and a data summary.

[February 19, 2009 - Information for Healthcare Professionals: Zonisamide (marketed as Zonegran, and generics) - FDA]


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