Antiprotozoal and Antiviral Chemotherapy for Malaria and Dengue

Vocabulary-style flashcards covering the pharmacology of antimalarial drugs and the supportive-care approach for dengue fever, as presented in the lecture notes.

P. falciparum

The most dangerous species of Plasmodium characterized by high fever, orthostatic hypotension, and capillary obstruction.

Hypnozoites

Dormant liver-stage parasites found in $P. vivax$ and $P. ovale$ that cause disease relapse if not eradicated.

Tissue Schizonticide

A classification of drugs, specifically Primaquine, used to eradicate liver hypnozoites for a radical cure.

Blood Schizonticide

Drugs such as Chloroquine, Artemisinin, Mefloquine, and Quinine that kill the asexual erythrocytic stage to terminate a clinical attack.

Gametocytocide

A drug, such as Primaquine or Pyrimethamine, that clears sexual forms of the parasite from the blood to block transmission to mosquitoes.

Chloroquine

A 4-aminoquinoline that concentrates in the parasite's food vacuole through ion trapping and inhibits heme polymerization into hemozoin.

Hemozoin

A harmless substance polymerized from toxic heme by malaria parasites; its formation is inhibited by drugs like Chloroquine and Quinine.

Retinopathy

A potential adverse effect of chronic Chloroquine use necessitating routine eye examinations.

Artemisinin

A drug derived from the qinghaosu plant that uses an endoperoxide bridge to generate free radicals that damage malarial proteins.

ACT (Artemisinin-based Combination Therapy)

A treatment strategy reserved for severe, multidrug-resistant $P. falciparum$ to protect the drug against developing resistance.

Primaquine

An 8-aminoquinoline used for radical cure of $P. vivax$ and $P. ovale$; it is contraindicated in pregnancy and carries a risk of hemolytic anemia in patients with G6PD deficiency.

Cinchonism

A reversible toxicity of Quinine characterized by nausea, tinnitus, and vertigo.

Positive Coombs test

A clinical finding requiring the suspension of Quinine therapy during malaria treatment.

Mefloquine

A drug with a long half-life of $17\,days$ used for multidrug-resistant $P. falciparum$, notable for neuropsychiatric side effects like hallucinations and depression.

Pyrimethamine

An antifolate that inhibits plasmodial dihydrofolate reductase, used as a blood schizonticide, a sporontocide, and as a treatment for toxoplasmosis.

Leucovorin

A medication used to reverse megaloblastic anemia caused by the antifolate effects of Pyrimethamine.

Dengue Virus (DENV)

A single-stranded RNA flavivirus with four serotypes transmitted by Aedes aegypti and Aedes albopictus mosquitoes.

Plasma Leakage

A dangerous manifestation of severe dengue indicated clinically by a rising hematocrit and a rapidly falling platelet count.

Paracetamol (Acetaminophen)

The analgesic and antipyretic of choice for dengue because it does not impair platelet function or vascular fragility.

NSAIDs and Aspirin

Analgesics that are strictly avoided in dengue treatment because they worsen bleeding risks and, in children, can cause Reye syndrome.