anti-protozoa_part 5 alternative_drugs_flashcards
What are the key features of tetracyclines as antimalarial drugs?
Tetracycline and doxycycline are active against erythrocytic schizonts of all human malaria parasites.
Not active against liver stages.
Effective for prophylaxis against multi-drug-resistant P. falciparum.
Effective in acute malaria when combined with quinine.
What is the role of clindamycin in malaria treatment?
Slowly active against the erythrocytic stage. Used with quinine for those in whom doxycycline is not recommended.
What are the key features of halofantrine?
Blood schizonticidal effective against erythrocytic stages of 4 species, including strains resistant to chloroquine.
Absorption is increased with food.
Metabolites are excreted in stool.
Used for the treatment of acute disease, mainlyfalciparum cerebral malaria.
What are the adverse effects of halofantrine?
Abdominal upsets. Transient increase in liver enzymes. Headache, cough, pruritus. Hemolytic anemia. Cardiac arrhythmia.
What are the key features of lumefantrine?
ed to halofantrine. Available in a fixed combination with artemether (Coartem). Absorption is variable and increased with food.
Highly effective in treating falciparum malaria but expensive. No cardiac toxicity.
What are the key features of Artemisinin?
A chemical extract of artemisia. Very rapidly acting blood schizonticides against all human malaria parasites. Has no effect on primary hepatic stages or hypnozoites. Can be used only orally. Converted in the liver into an active metabolite (dihydroartemisinin).
What are the types of Artemisinin analogs?
1) Artesunate: Water-soluble drug (Oral, IV, IM, rectal).
2) Artemether: Lipid-soluble drug (Oral, IM, rectal).
What are the uses of Artemisinin?
Monotherapy is not recommended. Combination therapies are preferred for increased efficacy and reduced resistance.
What are the adverse effects of Artemisinin?
Generally well tolerated. Common adverse effects include nausea, vomiting, dizziness. Rare serious toxicities include 1.neutropenia, anemia, hemolysis,
2.elevated liver enzymes,
3.transient heart block.
What are the key features of Atovaquone?
Acts against plasmodium by disrupting mitochondrial electron transport. Bioavailability is low (increased with food). High binding capacity (99%). Half-life is about 3 days. Excreted mainly as unchanged in the stool.
What are the uses of Atovaquone?
1) Not used alone (resistant parasites). 2) Combined with proguanil for both treatment and chemoprophylaxis of falciparum malaria.
What are the adverse effects of Atovaquone?
Nausea, vomiting, diarrhea, fever, rash, cough, headache, insomnia.
