A University of Kentucky College of Pharmacy faculty member has developed nasal and transdermal delivery systems for Zyban, a prescription drug in pill form used for smoking cessation and depression.
Abdul Houdi, Ph.D., assistant professor in the UK College of Pharmacy, has applied for a patent for his enhancement of the delivery of Zyban. The oral dosage of Zyban has very low bioavailabiltiy due to extensive inactivation by the liver prior to reaching the brain, the site of action, Houdi said. Also, the high level of Zyban metabolites formed after oral tablet administration may be associated with poor clinical outcome due to the metabolites adverse effects, he said. The most serious potential side effect is seizure, however, other side effects include anxiety, headache and fast or irregular heartbeat, he said.
"The nasal or transdermal delivery of Zyban will reduce the dose used in tablet form making it more tolerable and result in fewer side effects in treating patients suffering from depression or by smokers for addiction treatment," he said.
In addition, data Houdi collected indicates Zyban is rapidly and well-absorbed through the nasal passage and would increase its bioavailability, or site of action, at least
12 to 15 times compared to the oral tablet form currently on the market. Since the tablet form of Zyban is heavily metabolized by the liver, administration by the nasal or transdermal route also may help reduce interactions with other drugs, which are extensively metabolized by the liver, Houdi said.
Houdi has applied for two patents, one for the transdermal use of Zyban and the other for the nasal spray. Zyban, released by Glaxo-Wellcome in the summer of 1997, is the nation's leading smoking cessation prescription product.