Pharmacology of Antimalarials Flashcards
What is the MOA of Chloroquine?
Prevents the polymerization of heme to hemozoin. The accumulation of heme is toxic to the parasite
Describe the PK of Chloroquine.
PO administration, large Vd, longer half-life
What ADRs are associated with Chloroquine?
GI irritation, blurry vision, headache. High doses can cause irreversible eye and ear damage and myocardial depression
What ADRs are associated with Quinine?
Chinchonism, hemolysis, hypotension, QT prolongation, Blackwater fever
Describe the PK of Quinine.
PO administration, short half-life, Narrow TI
What is the first-line malarial prophylaxis in areas with resistant P. falciparum?
Mefloquine
Describe the PK or Mefloquine.
PO only, long half-life with weakly dosing
What anti-malarial drug accumulates to release toxic free radicals?
Artemisinin
Describe the PK of Artemisinin.
Very short half-life, rapid-acting
What is the only drug against quinine-resistant malaria strains?
Artemisinin
What is the most common adverse effect of Artemisinin?
GI discomfort
True/False. Artemisinin is used as a monotherapy for quinine-resistant malaria.
False. Artemisinin is never used as a monotherapy. Standard treatment combine Artemisinin with another anti-malarial drug
What anti-malarial is effective against all stages of the malaria parasite in the human body?
Primaquine & Tafenoquine
What drug should be used to prevent the relapse of a malaria infection?
Primaquine since it is effective against the gametocyte stage
Primaquine is generally well-tolerated, but is contraindicated/should be avoided in what patients?
GP6D deficiency, pregnancy
What is the MOA of Atovaquone?
Disrupts electron transport to reduce ATP and inhibit pyrimidine synthesis
Atovaquone is effective against what stages of the malaria life cycle?
Tissue & erythrocytic
What is the most effective prophylaxis against falciparum malaria?
Marlarone (Atrovaquone-Proguanil)
What is the MOA of antifolate anti-malarial drugs?
Inhibits dihydrofolate reductase
What is the MOA of protein synthesis inhibitor anti-malarial drugs?
Binds to the 30S or 50S subunit
What ADRs are associated with protein synthesis inhibitor anti-malarial drugs?
Photosensitivity, tooth discoloration in children, vaginal candidiasis, GI discomfort, esophagitis
What anti-malarial drugs are only effective against the erythrocytic (blood) stage?
Chloroquine, Artemisinin, Mefloquine
What is the recommended prophylaxis in areas without resistant P. falciparum?
Chloroquine
What is the standard treatment for chloroquine-resistant malaria?
Artemisinin
What is the standard treatment for multidrug-resistant malaria?
Quinine
