Lobeline is used in a variety of over-the-counter aids for smoking cessation but it has never been documented in scientific studies to be efficacious as an aid to cessation. Experimental data, however, suggests that it may be more effective in alternate formulations and/or presented at higher dose levels. Despite the wide spread use of lobeline there are little data on its kinetics or specific dose-related effects on human subjective and physiologic responses, and on its effects on cigarette smoking. The major purpose of the present study was to determine the safety of lobeline given intravenously over a period of 5 minutes in doses up to 8 mg. The present study also compared the effects of pretreatment of intravenously administered lobeline, placebo and nicotine on physiologic effects, subjective effects and kinetics. In addition, the effects of these drugs on cigarette smoking behavior was also evaluated. We have recently completed this study and are currently writing up the report. Four subjects completed the full dose-range of lobeline and nicotine with no adverse effects on either cardiovascular measures (ECG, blood pressure, heart rate) or other subjective effects. These results suggest that lobeline is safe even when given as a 5 min intravenous injection up to doses of 8 mg. Inspection of the subjective effects data suggest that doses administered were not producing any effects similar to standard drugs of abuse. Preliminary results also indicate that the doses of lobeline and nicotine administered using the injection procedure in the present study did not show any decreases on cigarette smoking behavior. At this time, plasma samples have yet to be analyzed so there are no kinetic data.
