口服劑型Nimodipine用於治療大腦蜘蛛膜下腔出血

FDA approves Nymalize—first nimodipine oral solution for use in certain brain hemorrhage patients For Immediate Release: May 14, 2013 Media Inquiries: Sandy Walsh, 301-796-4669, sandy.walsh@fda.hhs.gov Consumer Inquiries: 888-INFO-FDANew oral formulation may help reduce potentially fatal medication errors On May 10, the U.S. Food and Drug Administration approved Nymalize, a new nimodipine oral solution, to treat patients experiencing symptoms resulting from ruptured blood vessels in the brain (subarachnoid hemorrhage). Nimodipine previously was available only as a liquid-filled gel capsule.Subarachnoid hemorrhage is serious, life threatening bleeding that occurs in the subarachnoid space – the area between the brain and the thin tissues that cover the brain. Nimodipine is a medication given in a critical care setting to treat neurologic complications from subarachnoid hemorrhage. Over the years, the FDA has received reports of serious and sometimes fatal consequences from intravenous (IV) injection of the liquid contents of oral nimodipine capsules. IV administration of nimodipine meant for oral use can result in death, cardiac arrest, severe decreases in blood pressure and other heart-related complications. In August 2010, the agency reminded health care professionals about the risks of IV administration of nimodipine from oral capsules and in 2006 a Boxed Warning was added to the drug to warn against such use."Having an oral version of this product may help reduce the medication errors we've seen from erroneous intravenous administration of the contents of oral capsules," said Russell Katz, M.D., director of the Division of Neurology Products in the FDA's Center for Drug Evaluation and Research. "Nymalize is a liquid that is administered orally, or via nasogastric tube or gastric tube, and there is no need for a needle to be used, which is what caused past medication errors."Based on the potential of the oral formulation, Nymalize, to decrease or eliminate medication errors, the application received fast track designation and priority review. Fast track and priority review are two programs the FDA uses to make drugs rapidly available.The approval of Nymalize is based on clinical studies evaluating the use of nimodipine oral capsules in patients with subarachnoid hemorrhage. The most common adverse event observed in the studies was decreased blood pressure. A patient's blood pressure should be carefully monitored during treatment.Nymalize is made by Atlanta-based Arbor Pharmaceuticals Inc.Nimodipine binds specifically to L-type voltage-gated calcium channels. There are numerous theories about its mechanism in preventing vasospasm, but none are conclusive.Nimodipine (marketed by Bayer as Nimotop) is a dihydropyridine calcium channel blocker originally developed for the treatment of high blood pressure. It is not frequently used for this indication, but has shown good results in preventing a major complication of subarachnoid hemorrhage (a form of cerebral hemorrhage) termed vasospasm; this is now the main use of nimodipine.

Nimodipine用於大腦蜘蛛膜下腔出血之治療 劉俐婷、周美惠、林明芳 近十年來 ，鈣離子通道阻斷劑而nimodipine廣泛應用在大腦動脈瘤破裂引起之蜘蛛膜下腔出血 ，被視為防治其續發性腦血管痙攣及缺血性神經損傷不可或缺的一環。Nimodipine有口服錠劑及靜脈輸注液兩種劑型，二者療效相同，但因注射的藥費成本是口服的十倍之高，故腸胃道吸收功能正常者以口服治療比較符合成本效益。值得注意是，注射劑的使用會大幅提升臨床用藥的複雜性，因為靜脈點滴nimodipine所產生的周邊血管擴張作用，違反了臨床上維持腦灌流壓的處置通則，即升高血壓、增加體液容積及適度稀釋血液等。除此之外 ，nimodipine輸注液裡的酒精濃度比米酒還高，cefoperazone"cefmenoxime及metronidazole等跟酒精有交互作用的抗生素 ，若與nimodipine輸注液併用可能會引發disulfiram擬似反應。副作用方面 ，nimodipine造成的血壓遽降，應立即以補充體液及注射升壓劑處理 ，必要時須減量或停藥。交互作用方面，抗癲癇藥物phenytoin會加速nimodipine的代謝，而valproic acid則會抑制其代謝，併用期間應依據臨床反應來調整劑量。（臨床醫學 2003; 52: 136-43）