Monoamine oxidase inhibitors (MAOIs) are a class of drugs that inhibit the activity of one or both monoamine oxidase enzymes: monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B). They are best known as effective antidepressants, especially for treatment-resistant depression and atypical depression. They are also used to treat panic disorder, social anxiety disorder, Parkinson's disease, and several other disorders.
Phenelzine, sold under the brand name Nardil, among others, is a non-selective and irreversible monoamine oxidase inhibitor (MAOI) of the hydrazine class which is primarily used as an antidepressant and anxiolytic. Along with tranylcypromine and isocarboxazid, phenelzine is one of the few non-selective and irreversible MAOIs still in widespread clinical use. It is typically available in 15 mg tablets and doses usually range from 45–90 mg per day.
Tranylcypromine, sold under the brand name Parnate among others, is a monoamine oxidase inhibitor (MAOI). More specifically, tranylcypromine acts as nonselective and irreversible inhibitor of the enzyme monoamine oxidase (MAO). It is used as an antidepressant and anxiolytic agent in the clinical treatment of mood and anxiety disorders, respectively.
Isocarboxazid is a non-selective, irreversible monoamine oxidase inhibitor (MAOI) of the hydrazine class used as an antidepressant. Along with phenelzine and tranylcypromine, it is one of only three classical MAOIs still available for clinical use in the treatment of psychiatric disorders in the United States, though it is not as commonly employed in comparison to the others.
Moclobemide, sold under the brand names Amira, Aurorix, Clobemix, Depnil and Manerix among others, is a reversible inhibitor of monoamine oxidase A (RIMA) drug primarily used to treat depression and social anxiety. It is not approved for use in the United States, but is approved in other Western countries such as Canada, the UK and Australia. It is produced by affiliates of the Hoffmann–La Roche pharmaceutical company. Initially, Aurorix was also marketed by Roche in South Africa, but was withdrawn after its patent rights expired and Cipla Medpro's Depnil and Pharma Dynamic's Clorix became available at half the cost.
Nialamide is a non-selective, irreversible monoamine oxidase inhibitor (MAOI) of the hydrazine class that was used as an antidepressant. It was withdrawn by Pfizer several decades ago due to the risk of hepatotoxicity.
Iproniazid is a non-selective, irreversible monoamine oxidase inhibitor (MAOI) of the hydrazine class. It is a xenobiotic that was originally designed to treat tuberculosis, but was later most prominently used as an antidepressant drug. However, it was withdrawn from the market because of its hepatotoxicity. The medical use of iproniazid was discontinued in most of the world in the 1960s, but remained in use in France until its discontinuation in 2015.
Iproclozide is an irreversible and selective monoamine oxidase inhibitor (MAOI) of the hydrazine chemical class that was used as an antidepressant, but has since been discontinued. It has been known to cause fulminant hepatitis and there have been at least three reported fatalities due to administration of the drug.
Toloxatone (Humoryl) is an antidepressant launched in 1984 in France by Sanofi Aventis for the treatment of depression. It was discontinued in 2002. It acts as a selective reversible inhibitor of MAO-A (RIMA).
Bifemelane (INN) (Alnert, Celeport), or bifemelane hydrochloride (JAN), also known as 4-(O-benzylphenoxy)-N-methylbutylamine, is an antidepressant and cerebral activator that is widely used in the treatment of cerebral infarction patients with depressive symptoms in Japan, and in the treatment of senile dementia as well. It also appears to be useful in the treatment of glaucoma. Bifemelane acts as a monoamine oxidase inhibitor (MAOI) of both isoenzymes, with competitive (reversible) inhibition of MAO-A (Ki = 4.20 μM) (making it a reversible inhibitor of monoamine oxidase A (RIMA)) and non-competitive (irreversible) inhibition of MAO-B (Ki = 46.0 μM), and also acts (weakly) as a norepinephrine reuptake inhibitor. The drug has nootropic, neuroprotective, and antidepressant-like effects in animal models, and appears to enhance the cholinergic system in the brain.
Pheniprazine is an irreversible and nonselective monoamine oxidase inhibitor (MAOI) of the hydrazine chemical class that was used as an antidepressant in the 1960s. It was also used in the treatment of angina pectoris and schizophrenia. Pheniprazine has been largely discontinued due to toxicity concerns such as jaundice, amblyopia, and optic neuritis.
Mebanazine is a monoamine oxidase inhibitor (MAOI) of the hydrazine chemical class that was previously used as an antidepressant in the 1960s, but has since been withdrawn due to hepatotoxicity.
Metfendrazine, also known as methphendrazine, is an irreversible and nonselective monoamine oxidase inhibitor (MAOI) of the hydrazine chemical class. It was investigated as an antidepressant, but was never marketed.
Phenoxypropazine is an irreversible and non-selective monoamine oxidase inhibitor (MAOI) of the hydrazine family. It was introduced as an antidepressant in 1961, but was subsequently withdrawn in 1966 due to hepatotoxicity concerns.
Pivhydrazine, also known as pivalylbenzhydrazine and pivazide, is an irreversible and non-selective monoamine oxidase inhibitor (MAOI) of the hydrazine family. It was formerly used as an antidepressant in the 1960s, but has since been discontinued.
Safrazine (Safra) is a non-selective, irreversible monoamine oxidase inhibitor (MAOI) of the hydrazine class that was introduced as an antidepressant in the 1960s, but has since been discontinued.
Benmoxin, also known as mebamoxine, is an irreversible and nonselective monoamine oxidase inhibitor (MAOI) of the hydrazine class. It was synthesized in 1967 and was subsequently used as an antidepressant in Europe, but is now no longer marketed.
Caroxazone is an antidepressant which was formerly used for the treatment of depression but is now no longer marketed. It acts as a reversible monoamine oxidase inhibitor (RIMA) of both MAO-A and MAO-B subtypes, with five-fold preference for the latter.
Almoxatone (MD-780,236) is a selective and reversible inhibitor of MAO-B. It was patented as an antidepressant and antiparkinsonian agent but was never marketed.
Cimemoxin (INN), or cyclohexylmethylhydrazine, is a hydrazine monoamine oxidase inhibitor (MAOI) antidepressant which was never marketed.
