Suramin gambiense

Suramin is a sulfated naphthylamine that was introduced in the 1920s. It is the first-line therapy for early hemolymphatic African trypanosomiasis (especially T brucei gambiense infection), but because it does not enter the central nervous system, it is not effective against advanced disease. 

Pentamidine isethionate usually is given by IM injection or by slow IV infusion over 60 minutes in single doses of 1.7 to 4.5 mg/kg/day for a series of 10 days. However, alternative dosing schedules are common, and the coadministration of suramin on alternate days provides an alternative means of treating T. brucei gambiense infections. Because of failure to penetrate the CNS, pentamidine is not used to treat T. brucei rhodesiense, which affects the brain early in the course of infection. The drug is also ineffective in T. brucei gambiense infections once the CNS is involved. 

Suramin is the first-line therapy for early-stage T. brucei rhodesiense infection but generally is not used for early-stage T. brucei gambiense. Because only small amounts of the drug enter the brain, suramin is used primarily to treat early stages (before CNS involvement) of African trypanosomiasis. 

Suramin Drug of choice for hemolymphatic stage of trypanosomiasis (T brucei gambiense, T rhodesiense)... 

African trypanosomiasis (sleeping sickness) is spread by the tsetse fly and is caused by infection with either Trypanosoma gambiense or T. rbodesiense. Suramin kills the parasites in blood and lymphoid nodes hy an unknown mechanism and Is curative early in the disease. It does not cross the blood—brain barrier and is ineffective when there is neurological involvemenl. 

Four drugs are cmrendy in use. Suramine, discovered in 1921, is used in the initial phase of treatment of T.b. rhodesiense. Pentamidine, discovered in 1941, is used in treatment of the initial phase of T.b. gambiense sleeping sickness. 

Suramin is the drug of choice for the early hemolymphatic stage of both Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense infections before nervous system invasion occurs [17 ]. The dose is 15-20 mg/kg/week, given intravenously, up to a maximum single dose of 1 g. Suramin, which is excreted by the kidneys, binds to plasma proteins and can persist in the circulation in low concentrations for as long as 3 months. A single course for an adult is usually 5 g, never to exceed 7 g. The primary adverse reactions are fever, rash, conjunctivitis, renal insufficiency, abdominal pain, paresthesia, and muscle pain. 

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