Antiamoebic and other Antiprotozoal Drugs 359tained fever, lethargy and lymphadenitis,
progressive brain dysfunction.
Apart from imidazole derivative e.g.
metronidazole, tinidazole, nimorazole etc.
and other agents such as hydroxyquinolines,
iodine preparation (povidoneiodine) and
antifungal antibiotics e.g. clotrimazole (used
mainly as vaginal pessaries), there are some
other compounds which are mainly used in
the treatment of trypanosomiasis. They are:
Suramin 1 g each wk for 5 wks IV or 1 g on
day 1, 3, 7, 14, 21
Melarsoprol 3.6 mg/kg/day IV for 3-4 days
Eflornithine 100 mg/kg IV every 6 hrs for 14
days
Nifurtimox 8-10 mg/kg orally 3-4 months.SURAMIN
It is a sulfated napthylamine and used
as first line therapy for early
hemolymphatic African trypanosomiasis
(caused by T. brucei gambiense). It has very
tight protein binding and having short
initial half life but terminal half life is about
50 days and is excreted by kidney. It is also
used for chemoprophylaxis against African
trypanosomiasis.
Adverse effects include nausea,
vomiting, fatigue, dermatitis, fever,
photophobia, haemolytic anaemia,
albuminuria and hematuria.
MELARSOPROL
Chemically it is trivalent arsenical used
for advanced CNS African trypanosomiasis.
It is administered IV in propylene glycol and
after administration it is rapidly excreted. It
is highly toxic and used only in advanced
trypanosomiasis when no alternative is there.
Adverse effects include vomiting,
fever, abdominal pain, renal and cardiac
disease and encephalopathy characterized
by cerebral edema, seizures, coma (even
death).EFLORNITHINE
It is an inhibitor of ornithine decarboxylase
and is used as second line therapy for
advanced CNS African trypanosomiasis.
After oral or IV administration, peak plasma
level is reached rapidly and elimination half
life is approximately three hours.
It is effective against advanced T.
brucei gambiense infection.
Adverse effects include vomiting,
diarrhoea, leukopenia, thrombocytopenia,
anaemia and seizures.NIFURTIMOX
Chemically it is nitrofuran, used for
American trypanosomiasis which is
commonly known as ‘Chagas disease.’
After oral administration, it is well
absorbed and plasma half life is about three
hours.
Adverse effects include nausea,
vomiting, fever, rash, abdominal pain,
neuropathies and seizures.TRICHOMONIASIS
It is caused by Trichomonas vaginalis and is
mainly associated with vulvovaginitis
which is characterized by greenish yellow
and cheesy vaginal discharge.
The various agents used in trichomo-
niasis are metronidazole, tinidazole and
secnidazole which are already described
earlier. They produce 100% cure.
Other protozoal infection is giardiasis
which is caused by Giardia lamblia and the
drug of choice in its treatment are
imidazole derivatives.