Related compounds | Appearance White, opaque crystals | |
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Related alkanoic acids | ||
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.
Contents
Uses
Tiopronin is used primarily for cystinuria and is well known in the cystinuric community. Depending on the severity of a person's cystinuria, tiopronin may be taken for life, possibly starting in early childhood. The drug works by reacting with urinary cysteine to form a more soluble, disulfide linked, tiopronin-cysteine complex.
It may also be used for Wilson's disease (an overload of copper in the body), and has also been investigated for the treatment of arthritis, though tiopronin is not an anti-inflammatory.
Tiopronin is also sometimes used as a stabilizing agent for metal nanoparticles. The thiol group binds to the nanoparticles, preventing coagulation.
Side effects
Tiopronin may present a variety of side effects, which are broadly similar to those of D-penicillamine and other compounds containing active sulfhydryl groups. Its pharmokinetics have been studied.
Costs
In the U.S., the drug was marketed by Mission Pharmacal at $1.50 per pill, but the rights were bought by Retrophin, owned by Martin Shkreli, and the price increased to $30 per pill for a 100mg capsule. A potential alternative in treatment and costs has arisen with the drug 'Bucillamine'. There is now a low-cost alternative available from Imprimis Pharmaceuticals Inc., Tiopronin Delayed Release, at $7.68 for 100mg.