Melarsoprol

Melarsoprol (2--1,3,2-dithiarsolan-e-4-methanol) is a medicinal drug used in the treatment of African trypanosomiasis, also known as sleeping sickness. It is also sold under the trade names "Mel B" and "Melarsen Oxide-BAL". Melarsoprol is a highly dangerous treatment, only administered by injection under the supervision of a physician. It causes a range of side effects, among them convulsions, fever, loss of consciousness, rashes, bloody stools, nausea, and vomiting. It is fatal in and of itself in a significant percentage of cases. more...

Eflornithine is a more modern and far less dangerous treatment for sleeping sickness, but is expensive, not widely available on the market, and most of its supply comes from donations from its manufacturer. Melarsoprol is often refered to as "arsenic in antifreeze" due to its composition and its unpleasant effects on patients.

It is so caustic that it is administered in glass syringes; it will melt plastic syringes. This is not actually due to its arsenic content (which is not caustic), but the solvent propylene glycol in which it is presented.

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