Pilocarpine is an alkaloid extracted from plants of the genus Pilocarpus. The drug stimulates the muscarinic receptors (especially M3, which is expressed in smooth muscles and glands) and thus induces salivation, hypertension and water intake. Pilocarpine was appoved by FDA for the alleviation of symptoms of xerostomia in patients who have undergone radiation therapy to their head and neck cancer and in patients with Sjogren's Syndrome. Ophthalmic solution of the drug is prescribed for the treatment of glaucoma, ocular hypertension, postoperative elevated intraocular pressure, etc.

Sofinicline is a selective agonist of the a4b2 subtype of nAChR. It is under development by Abbott Laboratories in collaboration with NeuroSearch. It is produced as a capsule in doses of 1, 2 or 4 mg. Sofinicline is a full agonist of the a4b2 nAChR. It has high binding affinity, ~ 0.1 nM, for this receptor. Sofinicline is orally active and is metabolized hepatically. Sofinicline has been used in trials studying the treatment of ADHD, neuralgia, diabetic neuropathies, diabetic polyneuropathy, and diabetic neuropathic pain, among others.

Xanomeline (LY-246,708) is an orthosteric muscarinic acetylcholine receptor (mAChR) agonist, often referred to as M1/M4-preferring. It is also known to act as a M5 receptor antagonist. Xanomeline was studied in clinical trials phase I in schizophrenia. In Phase II clinical trials in Alzheimer’s patients, xanomeline significantly improved several measures of cognitive function, yet produced unwanted side effects that limited patient compliance. The side effects seem to be associated with rapid metabolism of the alkyloxy side chain following oral administration, resulting in a nonselective, yet active compound with limited therapeutic utility. Despite a second Phase II clinical trial with a patch formulation, the liabilities of xanomeline still outweigh its benefits.

Altinicline (SIB-1508Y, SIB-1765F) is a drug which acts as an agonist at neural nicotinic acetylcholine receptors with high selectivity for the α4β2 subtype. It stimulates release of dopamine and acetylcholine in the brain in both rodent and primate models, and progressed as far as Phase II clinical trials for Parkinson's disease, where "no antiparkinsonian or cognitive-enhancing effects were demonstrated", although its current status is unclear.

Pozanicline is an alpha4-beta2 neuronal nicotinic receptor partial agonist. It had been in phase II clinical trials for the treatment of attention hyperactivity disorder and Alzheimer’s disease. It was tested for the treatment of schizophrenia too. All these studies were discontinued. Modulation of hippocampal learning and memory using Pozanicline in animal model was effective as novel therapeutic strategies for nicotine addiction. However future clinical trial was terminated.

Revatropate is a muscarinic antagonist with selectivity for M1 and M3 receptor subtypes. Significant improvement in airway function was shown in horses with heaves after inhalation of revatropate, and it was found to be a safe and effective bronchodilator. Early clinical studies in chronic obstructive airway disease (COAD) patients also showed that inhaled revatropate was an effective bronchodilator, and well tolerated.

Alvameline is a partial agonist of the M1 mAChR that also displays M2/M3 antagonist effects. It readily crosses the blood-brain barrier. It has an effect profile that makes it of interest to test its ability to counteract bladder overactivity in humans. Behaviorally, alvameline has been shown to significantly improve Morris water maze (MWM) performance in both young and ageimpaired rats. It failed to improve cognition in patients with mild to moderate Alzheimer's disease.

ABT-594 [(R)-5-(2-azetidinylmethoxy)-2-chloropyridine] is a potent cholinergic neuronal nicotinic acetylcholine receptor (nAChR) ligand with analgesic properties. ABT-594 binds alpha-4/ beta-2 neuronal nAChRs acting as an agonist. ABT-594 is studying for the treatment of diabetic peripheral neuropathic pain.

Dianicline binds with high affinity to the rat and human alpha4beta2 nicotinic acetylcholine receptor (nAChR) subtypes and displays selectivity for the alpha4beta2 nAChR. Electrophysiological experiments indicate that dianicline is a partial agonist at the human alpha4beta2 nAChR subtype. Pretreatment with dianicline reduces the dopamine-releasing and discriminative effects of nicotine. Dianicline shows activity in animal models of nicotine dependence at doses devoid of unwanted side effects typically observed with nicotine. Dianicline did not increase cigarette smoking abstinence rates beyond the initial phase of treatment. However, self-reported craving and nicotine withdrawal symptoms were reduced. The most common adverse event for subjects receiving dianicline was nausea. Other gastrointestinal disorders also tended to be more frequent in the dianicline group, including diarrhea.