Effects of Selegiline on craving for nicotine
Initial Award Abstract
This pilot study has two primary aims: (1) to measure the effects of the selegiline transdermal system on blood pressure and heart rate in a group of regular cigarette smokers (N=10); (2) to examine the extent to which selegiline may reduce nicotine cravings and prevent smoking relapse. We believe that it is important to prevent or reduce nicotine craving because those who experience high levels of craving after they have quit smoking are more likely to begin smoking again. This proposal is very relevant to the TRDRP research priorities concerned with the study of medicines useful in the treatment of nicotine addiction and studies of the factors which make it difficult for people to stop smoking.
To realize these aims, ten smokers who report smoking 20+ cigarettes per day will be required to quit smoking for 24 hrs. Following cessation, they will be asked to wear a selegiline patch on a daily basis for a period of 4 consecutive weeks. Participants will be required to attend clinic each week of the 4 week study. At clinic visits we will measure vital signs (HR, BP), adverse events, nicotine withdrawal symptoms and expired-air carbon monoxide. Our interest in using selegiline to prevent or reduce craving is based upon research which indicates that a chemical in the body called dopamine has an important role to play in maintaining drug dependencies. Selegiline is a medication which helps to increase the amount of this chemical in the brain. As a result, it may be possible to reduce craving for nicotine (and other drugs) through use of selegiline and thereby making it less diffiult for smokers to quit. We will determine whether selegiline is useful by measuring the extent to which the medication reduces nicotine craving after study participants stop smoking and the extent to which participants are able to remain off cigarettes for the duration of the study..
This study would be the first to examine the effectivness of selegiline in preventing or reducing craving for nicotine and promoting smoking cessation. However, a current study administered by the National Institute on Drug Abuse, is now investigating the usefulness of selegiline as a treatment for cocaine abuse and craving. Given the substantial amount of evidence which indicates that nicotine produces dependence, this study promises to yield results which may have important clinical and theoretical implications for the treatment of nicotine dependence. |
The study was designed as a small-scale pilot to determine how well cigarette smokers would tolerate selegiline delivered via a skin patch over a period of 5 weeks. Selegiline is of interest because this medication may be able to reduce cravings that increase the likelihood that smokers will relapse after quitting.
Treatment: Nine participants received selegiline skin patches. They were instructed to apply patches every 24 hours for 28 consecutive days. The study medication was provided free of charge. Participants were required to visit the study clinic once each week for five weeks.
Adverse events/side effects. The medication appeared to be well-tolerated. A total of 18 side effects were reported during the course of the study. Side effects reported as "mild" were: Confusion (2), Dizziness (4), Difficulty Sleeping (2), Agitation (1), Headache (1), Dry Mouth (3), Difficulty Concentrating (1). Side effects reported as "moderate" were: Confusion (1), Dry Mouth (1). Side effects reported as "severe" were Anxiety (1) and Disorientation (1). Two participants discontinued treatment before Visit 2, one of these might be attributed to side effects of the medication (Anxiety).STS did not appear to have an impact on blood pressure or heart rate. Mean systolic and diastolic blood pressure and heart rate are given for each clinic visit. Baseline: 124/72, 78; V1: 124/71, 69; V2: 122/71, 74; 3: 122/71, 69; V4: 115/67, 70; V5: 118/72; 71.
Effects on amount smoked. Cigarette consumption was reduced over the course of the study. Mean number of cigarettes reported/day are given for each visit. Baseline: 23/day; V2: 3/day; V3: 4/day; V4: 7/day; V5: 4/day.
Effects on smoking The number of participants reporting abstinence for 24hrs at each visit was as follows: V1: 9/9; V2: 5/9; V3: 2/9; V4: 3/9; V5: 3/9. Reports of abstinence were confirmed by analyzing breath samples for carbon monoxide content.
Conclusions: Selegiline delivered via a transdermal system appeared to be well-tolerated when used for a period of 5 weeks by cigarette smokers. Side effects were relatively few and predominantly mild in nature as reported by participants. Two participants discontinued treatment early on but only one of these might be attributed to the effects of the medication. Participants reduced their level of cigarette consumption significantly over the course of treatment and 33% were abstinent at the final visit. In general, participants remarked that the medication had a marked calming effect that greatly eased the difficulty of making a quit attempt. This small-scale, open label trial was not designed to permit conclusions about the efficacy of the medication as an aid to cigarette smoking cessation. However, the results are interesting and suggest that future controlled investigations are warranted.
This pilot study has two primary aims: (1) to obtain safety data on the effects of a selegiline transdermal system in a cohort of regular cigarette smokers (N=10); (2) to examine the extent to which selegiline may reduce nicotine cravings and prevent smoking relapse.
Smokers who report smoking 20+ cigarettes per day (N =10) will be required to quit smoking for 24 hrs. Following cessation, they will be asked to wear a selegiline patch on a daily basis for a period of 4 consecutive weeks.
Participants will be required to visit the clinic once per week during the course of the study. The study schedule is presented below. |