Antimalarials Flashcards
P. Vivax Incubation Period
2-17 days
P. Falciparum incubation Period
9-14 days
P. ovale Incubation Period
16-18 days
P. malarial incubation period
18-40 days
Lab diagnosis for Malria
Thick or thin smear. Thick for parasite, thin for gametocytes
Antimalarial Drugs
- Chloroquine
- Quinine and Quinidine
- Mefloquine
- Primaquine
- Atovaquone
- Sulfadoxine-pyrimethamine • Doxycycline
- Artemisinins
Chloroquine Clinical Applications
- Drug of choice in the treatment of non-falciparum and sensitive uncomplicated falciparum malaria
- Preferred chemoprophylactic agent in areas without resistant falciparum malaria
Chloroquine MOA
Prevents biocrystallization of hemoglobin breakdown product heme to non-toxic hemozoin
Chloroquine Resistance
P. falciparum: mutations in putative transporter, PfCRT
Chloroquine AE
- Pruritus (common in Africans)
- Nausea, vomiting, abdominal pain, headache, anorexia, malaise, blurring of vision, urticaria (uncommon)
- Hemolysis (G6PD-deficient people)
- Can cause electrocardiographic changes
Chloroquine Contraindications
• psoriasis or porphyria (may precipitate attacks), retinal or visual field abnormalities.
SAFE IN PREGNANCY & YOUNG CHILDREN
Quinine & Quinidine Clinical Applications
- Parenteral treatment of severe falciparum malaria (Quinidine)
- Oral treatment of falciparum malaria (alternative in chloroquine-resistant areas) (Quinine)
Quinine & Quinidine MOA
- Depresses O2 uptake and carbohydrate metabolism
2. Intercalates into DNA, disrupting parasite’s replication and transcription
Quinine & Quinidine Adverse Effects
- Cinchonism: tinnitus, headache, nausea, dizziness, flushing & visual disturbances
- Hypersensitivity: skin rashes, urticaria, angioedema, bronchospasm
- Hematologic abnormalities: hemolysis (G6PD deficiency), leukopenia, agranulocytosis, thrombocytopenia
- Hypoglycemia: stimulation of insulin release
- Uterine contractions: still used in treatment of severe falciparum malaria in pregnancy
- Severe hypotension: too rapid IV infusion
- ECG abnormalities: QT prolongation
- Blackwater fever: hemolysis & hemoglobinuria (likely hypersensitivity reaction)
Quinine & Quinidine Contraindications
- Do not use concurrently with mefloquine
- Can raise plasma levels of warfarin & digoxin
- Reduce dose in renal insufficiency
- FDA category C in pregnancy