From Wikipedia, the free encyclopedia
Jump to: navigation, search
Systematic (IUPAC) name
Clinical data
AHFS/ Micromedex Detailed Consumer Information
Pregnancy cat.
  •  ?
Legal status
  •  ?
Routes IV
Pharmacokinetic data
Bioavailability ?
Metabolism ?
Half-life 35 hours
Excretion Renal
CAS number 494-79-1 N
ATC code P01CD01 QP51AD04
PubChem CID 10311
ChemSpider 9889 YesY
UNII ZF3786Q2E8 YesY
KEGG D00832 YesY
Chemical data
Formula C12H15AsN6OS2 
Mol. mass 398.341 g/mol
 N (what is this?)  (verify)

Melarsoprol (INN) is a medicinal drug used in the treatment of East African, (AKA rhodesiense) human African trypanosomiasis.[1] It is also sold under the trade names “Mel B” and “Melarsen Oxide-BAL.”

Melarsoprol is also used in the treatment of trypanosomiasis, such as Chagas disease and West African sleeping sickness, the former caused by Trypanosoma cruzi and the latter by Trypanosoma brucei gambiense.

It is on the World Health Organization's List of Essential Medicines, a list of the most important medications needed in a basic health system.[2]

Side effects[edit]

Being a toxic organic compound of arsenic, melarsoprol is a highly dangerous treatment which is only administered by injection under the supervision of a physician, as it can produce similar effects as arsenic poisoning. Among clinicians, it is colloquially referred to as "Arsenic in antifreeze".[3]

It is known to cause a range of side effects including convulsions, fever, loss of consciousness, rashes, bloody stools, nausea, and vomiting. It causes encephalopathy in 5–10% of cases, of which 40% die.[4]


Eflornithine is a more modern and far less dangerous treatment for sleeping sickness,[5] but it is expensive, it is not widely available on the market, and most of its supply comes from donations from its manufacturer.[6]


  1. ^ Bisser S, N'Siesi FX, Lejon V et al. (2007). "Equivalence trial of melarsoprol and nifurtimox monotherapy and combination therapy for the treatment of second-stage Trypanosoma brucei rhodesiense sleeping sickness". J. Infect. Dis. 195 (3): 322–9. doi:10.1086/510534. PMID 17205469. 
  2. ^ "WHO Model List of EssentialMedicines". World Health Organization. October 2013. Retrieved 22 April 2014. 
  3. ^ Hollingham R (2005). "Curing diseases modern medicine has left behind". New Scientist 2005 (2482): 40–41. 
  4. ^ Balasegaram M, Harris S, Checchi F, Ghorashian S, Hamel C, Karunakara U (2006). "Melarsoprol versus eflornithine for treating late-stage Gambian trypanosomiasis in the Republic of the Congo". Bulletin of the World Health Organization 84 (10): 783–791. doi:10.1590/S0042-96862006001000012. PMC 2627491. PMID 17128358. 
  5. ^ Chappuis F, Udayraj N, Stietenroth K, Meussen A, Bovier PA (2005). "Eflornithine is safer than melarsoprol for the treatment of second-stage Trypanosoma brucei gambiense human African trypanosomiasis". Clin. Infect. Dis. 41 (5): 748–751. doi:10.1086/432576. PMID 16080099. 
  6. ^ J. Robays, M. E. Raguenaud, T. Josenando, M. Boelaert (2008). "Eflornithine is a cost-effective alternative to melarsoprol for the treatment of second-stage human West African trypanosomiasis in Caxito, Angola". Tropical Medicine and International Health 13 (2): 265–271. doi:10.1111/j.1365-3156.2007.01999.x. PMID 18304274.