What is "tiopronin"

n. A thiol drug used to control the rate of cystine precipitation and excretion in cystinuria.

Tiopronin (trade name Thiola) is a prescription thiol drug used to control the rate of cystine precipitation and excretion in the disease cystinuria. Due to the rarity of the disorder, tiopronin falls under the classification of an orphan drug. It is somewhat similar to penicillamine in both chemistry and pharmacology.