Pilocarpus pennatifolius is known, along the Amazon river, as jaborandi. In English, we call it by a translation of that word; "slobber weed." It does exactly what it says.
In Brazil, it is occasionally taken to bring on sweat and to cure dry mouth. It certainly does the latter. Someone who chomps down on slobber weed is sometimes forced to bend with their head over a bucket as they bring up pints of saliva. They drool continuously for hours. Some have to be kept hydrated by doctors.
People used to think that this was the result of irritation to the mouth that was flushed by saliva. Actually, slobber weed hacks your parasympathetic nervous system. Tears, urination, digestion, and even sexual arousal are known to be associated with the secretion of liquids. The parasympathetic nervous system is in charge of that. It takes charge, in part, with the neurotransmitter acetylcholine. This is remarkably similar – as far as the nervous system is concerned – to the alkaloid pilocarpine, which resides in slobber weed. Once the weed is ingested, the body reacts as if the parasympathetic nervous system has issued an insistent command to produce drool.
This plant occasionally freaks out horse owners, as sometimes horses will eat some of the weed and drool for days. Although it might be pleasurable to contemplate adding a bit of slobber weed to someone's dish, things can get more serious than just sweating and drool. Dizziness, nausea, and prolonged sickness can also kick in. Perhaps it's best to just know your power over others without using it.