Antiandrogens such as cyproterone acetate and medroxyprogesterone acetate, or the LHRH agonist leuprolide, are sometimes prescribed to convicted male sex offenders who are released on parole in an effort to stop them reoffending, in a treatment sometimes referred to as chemical castration, however the high doses required often cause a range of side effects which may limit compliance.
Barrister Sir Edward Marshall Hall theorised that murderer Hawley Harvey Crippen was using hyoscine on his wife as an anaphrodisiac but accidentally gave her an overdose and then panicked when she died.
The mechanism of the active component of some plant-based anaphrodisiacs may be the inhibition of enzymes that catalyze the conversion of sex-hormone precursors into androstenedione, which promotes the reduction of sexual urges.
The amino acid 5-HTP, or 5-hydroxytryptophan, has been anecdotally reported to be a mild anaphrodisiac, as has the serotonergic empathogen MDMA, popularly known as "ecstasy".
In addition, other serotonergic euphoriant drugs, like the psychedelic LSD, have been reportedly used to drastically increase sexual pleasure.
A PDE5 inhibitor taken alone has no effect on sex drive, suggesting that serotonergic euphoriants like MDMA may actually increase libido while decreasing performance, similar to alcohol.
However, the study also showed that the level of testosterone normalizes after abstinence of liquorice within a few days and the effects completely disappear.