Modafinil acid (code name CRL-40467), also known as modafinilic acid or modafinil carboxylate, is one of the two major metabolites of

modafinil Modafinil, sold under the brand name Provigil among others, is a central nervous system (CNS) stimulant and wakefulness-promoting agent, eugeroic (wakefulness promoter) medication used primarily to treat narcolepsy, a sleep disorder characteri ...

– the other being modafinil sulfone. Modafinil acid is also a metabolite of the modafinil

prodrug A prodrug is a pharmacologically inactive medication or compound that, after intake, is metabolized (i.e., converted within the body) into a pharmacologically active drug. Instead of administering a drug directly, a corresponding prodrug can be ...

, adrafinil, and the (''R'')-(–)-

enantiomer In chemistry, an enantiomer (Help:IPA/English, /ɪˈnænti.əmər, ɛ-, -oʊ-/ Help:Pronunciation respelling key, ''ih-NAN-tee-ə-mər''), also known as an optical isomer, antipode, or optical antipode, is one of a pair of molecular entities whi ...

is a metabolite of

armodafinil Armodafinil, sold under the brand name Nuvigil, is a wakefulness-promoting medication which is used to treat excessive daytime sleepiness associated with obstructive sleep apnea, narcolepsy, and shift work disorder. It is also used off-label ...

, the (''R'')-(–)-enantiomer of modafinil. Between 30 - 60% of modafinil is converted to modafinil acid and its half life is roughly half that of modafinil (about 7 hours). Modafinil acid seems to be inactive, and similarly to modafinil sulfone, does not appear to contribute to the wakefulness-promoting/

psychostimulant Stimulants (also known as central nervous system stimulants, or psychostimulants, or colloquially as uppers) are a class of drugs that increase alertness. They are used for various purposes, such as enhancing attention, motivation, cognition ...

effects of modafinil. In the breakdown process of modafinil, modafinil is primarily

hydrolyzed Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysi ...

by an

esterase In biochemistry, an esterase is a class of enzyme that splits esters into an acid and an alcohol in a chemical reaction with water called hydrolysis (and as such, it is a type of hydrolase). A wide range of different esterases exist that differ ...

amidase In enzymology, an amidase (, ''acylamidase'', ''acylase (misleading)'', ''amidohydrolase (ambiguous)'', ''deaminase (ambiguous)'', ''fatty acylamidase'', ''N-acetylaminohydrolase (ambiguous)'') is an enzyme that catalysis, catalyzes the hydrolysis ...

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

into modafinil acid. The apparent clearance of modafinil acid is significantly higher than that of modafinil, following the hypothesis that metabolism increases the polarity and the clearance of modafinil.

References

Carboxylic acids Human drug metabolites Sulfoxides Modafinil analogues {{nervous-system-drug-stub

See also

References