The drug combination fenfluramine/phentermine, usually called fen-phen, is an anti-obesity medication that is no longer widely available. It was sold in the early 1990s, and utilized two anorectics. Fenfluramine was marketed by American Home Products as Pondimin, but was shown to cause potentially fatal pulmonary hypertension and heart valve problems, which eventually led to its withdrawal in 1997 and legal damages of over $13 billion. Phentermine was not shown to have harmful effects.
Pergolide, sold under the brand name Permax and Prascend (veterinary) among others, is an ergoline-based dopamine receptor agonist used in some countries for the treatment of Parkinson's disease. Parkinson's disease is associated with reduced dopamine synthesis in the substantia nigra of the brain. Pergolide acts on many of the same receptors as dopamine to increase receptor activity.
Fenfluramine, sold under the brand name Fintepla, is a serotonergic medication used for the treatment of seizures associated with Dravet syndrome and Lennox–Gastaut syndrome. It was formerly used as an appetite suppressant in the treatment of obesity, but was discontinued for this use due to cardiovascular toxicity before being repurposed for new indications. Fenfluramine was used for weight loss both alone under the brand name Pondimin and in combination with phentermine commonly known as fen-phen.
Methylergometrine, also known as methylergonovine and sold under the brand name Methergine, is a medication of the ergoline and lysergamide groups which is used as an oxytocic in obstetrics and as an antimigraine agent in the treatment of migraine headaches. It reportedly produces psychedelic effects similar to those of lysergic acid diethylamide (LSD) at high doses.
Methysergide, sold under the brand names Deseril and Sansert, is a monoaminergic medication of the ergoline and lysergamide groups which is used in the prophylaxis and treatment of migraine and cluster headaches. It has been withdrawn from the market in the United States and Canada due to safety concerns. It is taken by mouth.
Aminorex is a weight loss (anorectic) stimulant drug. It was withdrawn from the market after it was found to cause pulmonary hypertension. In the U.S., it is an illegal Schedule I drug, meaning it has high abuse potential, no accepted medical use, and a poor safety profile.
A serotonin receptor agonist is an agonist of one or more serotonin receptors. They activate serotonin receptors in a manner similar to that of serotonin, a neurotransmitter and hormone and the endogenous ligand of the serotonin receptors.
meta-Chlorophenylpiperazine (mCPP) is a psychoactive drug of the phenylpiperazine class. It was initially developed in the late-1970s and used in scientific research before being sold as a designer drug in the mid-2000s. It has been detected in pills touted as legal alternatives to illicit stimulants in New Zealand and pills sold as "ecstasy" in Europe and the United States.
Chlorphentermine, sold under the brand names Apsedon, Desopimon, and Lucofen, is a serotonergic appetite suppressant of the amphetamine family. Developed in 1962, it is the para-chloro derivative of the better-known appetite suppressant phentermine, which is still in current use.
Cardiac fibrosis commonly refers to the excess deposition of extracellular matrix in the cardiac muscle, but the term may also refer to an abnormal thickening of the heart valves due to inappropriate proliferation of cardiac fibroblasts. Fibrotic cardiac muscle is stiffer and less compliant and is seen in the progression to heart failure. The description below focuses on a specific mechanism of valvular pathology but there are other causes of valve pathology and fibrosis of the cardiac muscle.
Naphthylaminopropane (PAL-287) is an experimental drug under investigation as of 2007 for the treatment of alcohol and stimulant addiction.
Benfluorex, sold under the brand name Mediator, is an anorectic and hypolipidemic agent that is structurally related to fenfluramine. It may improve glycemic control and decrease insulin resistance in people with poorly controlled type-2 diabetes.
5-Hydroxytryptamine receptor 2B (5-HT2B) also known as serotonin receptor 2B is a protein that in humans is encoded by the HTR2B gene. 5-HT2B is a member of the 5-HT2 receptor family that binds the neurotransmitter serotonin (5-hydroxytryptamine, 5-HT). Like all 5-HT2 receptors, the 5-HT2B receptor is Gq/G11-protein coupled, leading to downstream activation of phospholipase C.
A serotonin releasing agent (SRA) is a type of drug that induces the release of serotonin into the neuronal synaptic cleft. A selective serotonin releasing agent (SSRA) is an SRA with less significant or no efficacy in producing neurotransmitter efflux at other types of monoamine neurons, including dopamine and norepinephrine neurons.
Serotonin antagonist and reuptake inhibitors (SARIs) are a class of drugs used mainly as antidepressants, but also as anxiolytics and hypnotics. They act by antagonizing serotonin receptors such as 5-HT2A and inhibiting the reuptake of serotonin, norepinephrine, and/or dopamine. Additionally, most also antagonize α1-adrenergic receptors. The majority of the currently marketed SARIs belong to the phenylpiperazine class of compounds.
PRX-08066 is a drug discovered and developed by Predix Pharmaceuticals [Dale S. Dhanoa et al. Patent US 7,030,240 B2], which acts as a potent and selective antagonist at the serotonin 5-HT2B receptor, with a 5-HT2Bbinding affinity (Ki) of 3.4nM, and high selectivity over the closely related 5-HT2A and 5-HT2C receptors and other receptor targets. PRX-08066 and other selective 5-HT2B antagonists are being researched for the treatment of pulmonary arterial hypertension, following the discovery that the potent 5-HT2B agonist norfenfluramine produces pulmonary arterial hypertension and subsequent heart valve damage. In animal studies, PRX-08066 has been found to reduce several key indicators of pulmonary arterial hypertension and improved cardiac output, with similar efficacy to established drugs for this condition such as bosentan, sildenafil, beraprost and iloprost. It is also being researched for potential anti-cancer applications, due to its ability to inhibit fibroblast activation.
5-APB is an empathogenic psychoactive compound of the substituted benzofuran, substituted amphetamine and substituted phenethylamine classes. 5-APB and other compounds are sometimes informally called "Benzofury".
Levofenfluramine (INN), or (−)-3-trifluoromethyl-N-ethylamphetamine, also known as (−)-fenfluramine or (R)-fenfluramine, is a drug of the amphetamine family that, itself (i.e., in enantiopure form), was never marketed. It is the levorotatory enantiomer of fenfluramine, the racemic form of the compound, whereas the dextrorotatory enantiomer is dexfenfluramine. Both fenfluramine and dexfenfluramine are anorectic agents that have been used clinically in the treatment of obesity (and hence, levofenfluramine has been as well since it is a component of fenfluramine). However, they have since been discontinued due to reports of causing cardiovascular conditions such as valvular heart disease and pulmonary hypertension, adverse effects that are likely to be caused by excessive stimulation of 5-HT2B receptors expressed on heart valves.
5-HT2C receptor agonists are a class of drugs that activate 5-HT2C receptors. They have been investigated for the treatment of a number of conditions including obesity, psychiatric disorders, sexual dysfunction and urinary incontinence.
VU0530244 is a potent, selective, and putatively peripherally restricted serotonin 5-HT2B receptor antagonist which was first described in 2023. Another similar drug, VU0631019, was also described alongside VU0530244. They were identified via high-throughput screening (HTS).
