Priapism

Question 1

Priapism is the term given to a persistent and painful erection. This is usually in males but can also occur in the clitoris.

A number of drugs are known to causes this (albeit rarely). The main groups are the antipsychotics and antidepressants.

Alpha blockade is generally considered to be the main mechanism that causes priapism but other mechanisms such as one mediated by serotonin have been suggested. This is to account for drugs such as citalopram which have also been associated with priapism.

Those drugs most associated with priapism (and which therefore tend to be exam favourites) include:

Answer 1

Trazodone
Chlorpromazine
Thioridazine

Question 2

Treatment

Answer 2

Treatment is via the use of alpha-adrenergic agonists, either as tablets or by injecting them into the penis! This is a serious condition and there is a case report in the literature of it leading to a man having his penis amputated! Thankfully it’s very rare.
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