The study examined the effects of three anti-epileptic drugs – carbamazepine, oxcarbazepine and valproic acid – on nicotine and nicotine metabolite levels in 149 smokers with schizophrenia and bipolar disorder.
“We believe this is the first report of either carbamazepine or oxcarbazepine causing a clinically significant interaction with nicotine metabolism,” study author Jill M. Williams, M.D., an associate professor of psychiatry and director of the Division of Addiction Psychiatry at UMDNJ-Robert Wood Johnson Medical School, said.
Smoking is more prevalent in people with serious forms of mental illnesses, such as schizophrenia and bipolar disorder, than in the general population, explained Kunal K. Gandhi, M.B.B.S., M.P.H., an instructor of psychiatry at the UMDNJ-Robert Wood Johnson Medical School and study co-author.
“The effect of these medications may have serious implications on nicotine metabolism and smoking behavior,” Williams added.
“Anti-epileptic drugs (AED) are of particular concern with respect to drug interactions because of their potential to induce many hepatic cytochrome P450 enzymes and increases nicotine metabolism,” Williams explained. “We will need to do more studies to see if carbamazepine or oxycarbamazepine affect smoking behavior or intake of tobacco smoke from cigarettes in groups of smokers who may or may not have mental illness, but they could increase smoking as well as craving for nicotine.”
AEDs are commonly used as adjunctive treatment for conditions other than epilepsy, including schizophrenia and bipolar disorder. This has implications for smokers using these medications and seeking smoking cessation treatment, Williams noted.
“Although the study was conducted in smokers with mental illness, it is unlikely that this effect was due to mental illness alone since we have found no difference in nicotine metabolite ratios in our other studies of smokers with mental illness not taking these drugs,” Williams added.
Reporters interested in interviewing Jill M. Williams, M.D., or Kunal K. Gandhi, M.B.B.S., M.P.H., should contact Zenaida Mendez, at (973) 972-7273 or firstname.lastname@example.org, or Jennifer Forbes, at (732) 235-6356 or email@example.com.
The University of Medicine and Dentistry of New Jersey (UMDNJ) is the nation’s largest free-standing public health sciences university with more than 6,000 students attending the state’s three medical schools, its only dental school, a graduate school of biomedical sciences, a school of health related professions, a school of nursing and its only school of public health on five campuses. Annually, there are more than two million patient visits at UMDNJ facilities and faculty practices at campuses in Newark, New Brunswick/Piscataway, Scotch Plains, Camden and Stratford. UMDNJ operates University Hospital, a Level I Trauma Center in Newark, and University Behavioral HealthCare, which provides a continuum of healthcare services with multiple locations throughout the state.