In a study consisting of a rat trial and a human trial, University of Pennsylvania researchers studied the effects of two acetylcholinesterase inhibitors, or AChEIs, called galantamine and donepezil on overall nicotine intake.

The rat component showed that pretreating the rodents with an AChEI decreased their nicotine consumption. Consistent with these effects, clinical trial participants taking the AChEI, not the placebo, smoked 2.3 fewer cigarettes daily, a 12% decrease, and noted feeling less satisfied with the cigarettes they did smoke.

Researchers divided a group of rats into galantamine and donepezil cohorts. To mirror voluntary drug taking in humans, the rats self-administered nicotine using a lever pushed at will. Once nicotine-taking stabilized, the rats were pretreated with one of the two AChEIs.

For both drugs, “we were able to show a reduction in total nicotine self-administered,” researchers said. However, there was a caveat. “We know from the literature that upward of 30% of patients will report nausea and vomiting [when taking these drugs], and this will limit their compliance,” researchers said.