藥物警訊

Onfi (clobazam): Drug Safety Communication - Risk of Serious Skin Reactions

AUDIENCE: Neurology, Pharmacy, Dermatology

ISSUE: FDA is warning the public that the anti-seizure drug Onfi (clobazam) can cause rare but serious skin reactions that can result in permanent harm and death. FDA approved changes to the Onfi drug label and the patient Medication Guide to describe the risk of these serious skin reactions.

These skin reactions, called Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), can occur at any time during Onfi treatment. However, the likelihood of skin reactions is greater during the first 8 weeks of treatment or when Onfi is stopped and then re-started. All cases of SJS and TEN in the FDA case series have resulted in hospitalization, one case resulted in blindness, and one case resulted in death. See the FDA Drug Safety Communication for a Data Summary and additional information.

The Onfi drug label has been revised to add information about the risk for serious skin reactions to the Warnings and Precautions section and to the Medication Guide.

BACKGROUND: Onfi is a benzodiazepine medication used in combination with other medicines to treat seizures associated with a severe form of epilepsy called Lennox-Gastaut Syndrome.

RECOMMENDATION: Patients should be closely monitored for signs or symptoms of SJS/TEN, especially during the first 8 weeks of treatment or when re-introducing therapy. Health care professionals should discontinue use of Onfi and consider an alternate therapy at the first sign of rash, unless it is clearly not drug-related.

Patients taking Onfi should seek immediate medical treatment if they develop a rash, blistering or peeling of the skin, sores in the mouth, or hives. Patients should not stop taking Onfi without first talking to their health care professionals. Stopping Onfi suddenly can cause serious withdrawal problems, such as seizures that will not stop, hallucinations, shaking, nervousness, and stomach or muscle cramps.

Healthcare professionals and patients are encouraged to report adverse events or side effects related to the use of these products to the FDA's MedWatch Safety Information and Adverse Event Reporting Program:

‧ Complete and submit the report Online: www.fda.gov/MedWatch/report.htm

‧ Download form or call 1-800-332-1088 to request a reporting form, then complete and return to the address on the pre-addressed form, or submit by fax to 1-800-FDA-0178

Read the MedWatch safety alert, including links to the FDA Drug Safety Communication and prescribing information (label) at:

http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHuma...

FDA告知大眾，抗癲癇藥品Onfi (clobazam)可能會造成罕見但嚴重之皮膚反應，並導致永久性傷害或死亡。FDA已核准變更藥品仿單和病人用藥須知，增加可能發生嚴重皮膚反應的風險的相關說明。

服用Onfi期間可能會發生史帝芬強生症候群候群 (Stevens-Johnson syndrome, SJS)，和毒性表皮壞死溶解症 (toxic epidermal necrolysis, TEN)等皮膚反應，常發生在開始治療時的前八週或再次投藥時。所有FDA接獲的SJS和TEN案例皆須住院接受治療，其中一名失明，另一名則死亡。

目前Onfi之藥品仿單已於警語及注意事項欄中加入有關發生此嚴重皮膚反應風險的資訊。

背景：Onfi 為benzodiazepine類藥物，與其他藥品併用於治療Lennox-Gastaut症候群。

建議：醫療人員應密切觀察病人是否有出現相關症狀，尤其是在療程開始的前八週或當重新投藥時。當病人出現疑似症狀時，除非可明顯認定與藥品無關，否則應立即停止用藥並更換其他替代藥品。

正服用Onfi之病人若自覺出現皮膚起疹、起泡或脫皮，口瘡或蕁麻疹，應立即與醫療人員聯絡。病人不應在尚未與醫療人員確認前自行停藥，停止服用此藥可能會造成嚴重的停藥問題，如癲癇再發作、產生幻覺、顫抖、緊張，和胃或肌肉痙攣。

相關訊息與連結請參考FDA網址：http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm377340.htm

資料來源：美國FDA之藥物安全警訊

資料提供：台大醫院藥劑部