Experimental antidepressants

Lysergic acid diethylamide, commonly known as LSD (from German ) and by the nicknames acid and lucy, is a semisynthetic hallucinogenic drug derived from ergot, known for its powerful psychological effects and serotonergic activity. It was historically used in psychiatry and 1960s counterculture; it is currently legally restricted but receiving renewed scientific interest and increasing use.

Ketamine is a cyclohexanone-derived general anesthetic and NMDA receptor antagonist with analgesic and hallucinogenic properties, used medically for anesthesia, depression, and pain management. Ketamine exists as its two enantiomers, S- (esketamine) and R- (arketamine), and has antidepressant action likely involving other mechanisms in addition to NMDA antagonism.

3,4-Methylenedioxymethamphetamine (MDMA), commonly known as ecstasy (tablet form), and molly (crystal form), is an entactogen with stimulant and minor psychedelic properties.

Psilocybin, also known as '4-phosphoryloxy-N,N-dimethyltryptamine (4-PO-DMT'), is a naturally occurring tryptamine alkaloid and investigational drug found in more than 200 species of mushrooms, with hallucinogenic and serotonergic effects. Effects include euphoria, changes in perception, a distorted sense of time, and perceived spiritual experiences. It can also cause adverse reactions such as nausea and panic attacks.

Tramadol, sold under the brand name Tramal among others, is an opioid pain medication and a serotonin–norepinephrine reuptake inhibitor (SNRI) used to treat moderate to severe pain. When taken by mouth in an immediate-release formulation, the onset of pain relief usually begins within an hour. It is also available by injection. It is available in combination with paracetamol (acetaminophen).

Scopolamine, also known as hyoscine, or '''Devil's Breath''', is a medication used to treat motion sickness and postoperative nausea and vomiting. It is also sometimes used before surgery to decrease saliva. When used by injection, effects begin after about 20 minutes and last for up to 8 hours. It may also be used orally and as a transdermal patch since it has been long known to have transdermal bioavailability.

Dimethyltryptamine (DMT), also known as '''N,N-dimethyltryptamine (N,N-DMT'''), is a serotonergic hallucinogen and investigational drug of the tryptamine family that occurs naturally in many plants and animals. DMT is used as a psychedelic drug and prepared by various cultures for ritual purposes as an entheogen.

Β-lactam molecule used as β-lactamase inhibitor to overcome antibiotic resistance in bacteria

Pramipexole, sold under the brand Mirapex among others, is a medication used to treat Parkinson's disease and restless legs syndrome. In Parkinson's disease it may be used alone or together with levodopa. It is taken by mouth. Pramipexole is a dopamine agonist of the non-ergoline class.

Lisdexamfetamine, sold under the brand names Vyvanse (, ) and Elvanse among others, is a stimulant medication that is used as a treatment for attention deficit hyperactivity disorder (ADHD) in both children and adults, and for moderate-to-severe binge eating disorder in adults. A prodrug of dextroamphetamine, lisdexamfetamine is taken by mouth. Its effects generally begin within 90 minutes and last for up to 14 hours.

Pimavanserin, sold under the brand name Nuplazid, is an atypical antipsychotic which is approved for the treatment of Parkinson's disease psychosis. It is taken by mouth.

'''para-Chloroamphetamine (PCA), also known as 4-chloroamphetamine (4-CA'''), is a serotonin–norepinephrine–dopamine releasing agent (SNDRA) and serotonergic neurotoxin of the amphetamine family. It is used in scientific research in the study of the serotonin system, as a serotonin releasing agent (SRA) at lower doses to produce serotonergic effects, and as a serotonergic neurotoxin at higher doses to produce long-lasting depletions of serotonin.

DOET, also known as 4-ethyl-2,5-dimethoxyamphetamine or as Hecate, is a psychedelic drug of the phenethylamine, amphetamine, and DOx families. It is closely related to DOM and is a synthetic analogue of the naturally occurring phenethylamine psychedelic mescaline. The drug is the derivative of DOM in which the methyl group at the 4 position has been replaced with a ethyl group. It is taken orally. DOET has a slow onset of 1 to 3hours, a delayed peak of 3 to 5hours, and a dose-dependent and potentially very long duration of 5 to 20hours.

Amdiglurax (), also known by its former developmental code names ALTO-100 and NSI-189 (short for "NeuralStem Inc. 189"), is a drug described as a hippocampal neurogenesis stimulant and indirect brain-derived neurotrophic factor (BDNF) modulator which is under development for the treatment of major depressive disorder (MDD), bipolar depression, and post-traumatic stress disorder (PTSD). There has also been interest in amdiglurax for possible treatment of cognitive impairment and neurodegeneration. It is taken by mouth.

Saredutant (SR-48,968) is a drug that acts as a NK2 receptor antagonist. It was under development by Sanofi-Aventis as a novel antidepressant and anxiolytic and made it to phase III clinical trials. However, in May 2009, Sanofi-Aventis published its quarterly results and announced the cessation of 14 research/development projects, among which was saredutant for the treatment of major depressive disorder.

4-Me-αMT (developmental code name MP-809), or 4-Me-AMT, also known as 4-methyl-α-methyltryptamine or as 4,α-dimethyltryptamine (4,α-DMT), is an experimental antidepressant of the tryptamine and α-alkyltryptamine families that was never marketed. It is closely structurally related to serotonergic psychedelics and entactogens like α-methyltryptamine (αMT) and α-ethyltryptamine (αET).

WAY-208466 is a potent and highly selective full agonist of the 5-HT6 receptor. It increases GABA levels in the cerebral cortex and tolerance does not appear to occur to this action upon chronic administration. Animal studies have shown that WAY-208466 produces antidepressant and anxiolytic effects in rodents and it may also be useful in the treatment of obsessive-compulsive disorder.

Zelquistinel (GATE-251, formerly AGN-241751) is an orally active small-molecule NMDA receptor modulator which is under development for the treatment of major depressive disorder (MDD) by Syndeio Biosciences, and previously by Allergan.

3β-Androstanediol, also known as 5α-androstane-3β,17β-diol, and sometimes shortened in the literature to 3β-diol, is an endogenous steroid hormone and a metabolite of androgens like dehydroepiandrosterone (DHEA) and dihydrotestosterone (DHT).

Alfetamine, or α-allyl-phenethylamine, is a chemical compound of the phenethylamine family. It was briefly investigated as a possible antidepressant in the early 1970s. Its activity profile was said to be very similar to imipramine and amitriptyline, two tricyclic antidepressants. It has now been largely superseded by the newer compounds in this class, and only rarely found in scientific literature. The "alpha" in its name refers to its prodrug form, alfetamine. In addition to being an antidepressant, alfetamine is also a neuroprotective agent that acts as a weak dopamine antagonist and a high

Arketamine (developmental code names PCN-101, HR-071603), also known as '(R)-ketamine or (R)-(−)-ketamine', is the (R)-(−) enantiomer of ketamine. Similarly to racemic ketamine and esketamine, the S(+) enantiomer of ketamine, arketamine is biologically active; however, it is less potent as an NMDA receptor antagonist and anesthetic and thus has never been approved or marketed for clinical use as an enantiopure drug. Arketamine is currently in clinical development as a novel antidepressant.

EX-597 (former developmental code names URB-597, KDS-4103, and ORG-231295) is a fatty acid amide hydrolase inhibitor (FAAH inhibitor) which is under development for the treatment of social anxiety disorder (or social phobia) and post-traumatic stress disorder (PTSD).