I assume you did something to alkalize the preparation. Arecoline is a weak base and will be charged at normal pH, so that, like the cocaine in coca leaves, it will be poorly absorbed unless an effort is made to change the pH
The molecule's structure makes it likely to work on acetylcholine receptors of which there are two types, muscarinic and nicotinic. It is believed to be a partial activator of muscarinic receptors, so that might have some mild hallucinogenic effects similar to Amanita muscaria. It's potential activity on nicotinic receptors has not been well studied, although its anthelmintic properties suggest that it may stimulate invertebrate nicotine receptors. For some unknown reason I do have a bottle of arecoline in the lab, although we have no record of having done experiments with it previously. We will go ahead and test it on a couple of human nicotine receptor subtypes probably later today (
http://papke.med.ufl.edu/index.html).