Antimalarials

Question 1

P. Falciparum

Answer 1

Malignant tertian malaria. Most lethal. Fever occurs every third day. No secondary tissue forms. Cerebral malaria. Has many drug resistant forms.

Question 2

P. Vivax

Answer 2

Benign tertian malaria. Fever occurs every third day. Has dormant forms in the liver (hypnozoites). Relapses for months/years. Duffy antigen was thought to be protective but isn’t.

Question 3

P. ovale

Answer 3

Rare. Has secondary tissue forms in the liver (hypnozoites). Relapses.

Question 4

P. Malariae

Answer 4

Quartan malaria. Fever occurs every four days. No tissue forms but can cause chronic infection.

Question 5

Blood Schizonticides

Answer 5

Act on RBC forms. Provide a clinical cure for vivax and ovale and a radical cure for malariae and faliparum.

Question 6

Tissue schizonticides

Answer 6

Act on the hepatic stages. Doesn’t effect the symptoms. Kill vivax and ovale to prevent relapse.

Question 7

Gametocidal agents

Answer 7

Eliminate proliferation. Doesn’t cure the disease just sloes the spread.

Question 8

Malaria DOC

Answer 8

Chloroquine

Question 9

Chloroquine (aralen) resistance

Answer 9

especially falciparum due to efflux pumps.

Question 10

Chloroquine MOA

Answer 10

Actively concentrate in plasmodia food vacule where they interfere with the degradation of hemoglobin producing a toxic by product.

Question 11

Chloroquine kinetics

Answer 11

Oral. accumulates in melanin-rich tissue. metabolized by CYP3A4.

Question 12

Cholorquine toxicity

Answer 12

retinal/corneal toxicity, ototoxicity, hemolysis (G6PD deficiency), QT prolongation.

Question 13

Cholorquine contraindications

Answer 13

psoriasis and porphyria.

Question 14

Mefloquine (Lariam) uses

Answer 14

Second-line drug for cholorquine-resistant strains.

Question 15

Mefloquine toxicity

Answer 15

1. ) depression of the myocardium, potential cardiac toxicity. (don’t combine with quinine).
2. ) seizures and aggravation of latent psychoses.
3. ) sleep and behavioral disturbances, vivid dreams
4. ) teratogenic

Question 16

Mefloquine contraindications

Answer 16

history of mental illness or epilepsy and pregnancy

Question 17

Quinine/Quinidine Gluconate uses

Answer 17

DOC for complicated chloroquine-resistant plasmodia and for unconscious patients.

Question 18

Quinine/Quinidine Gluconate kinetics

Answer 18

quinine=oral quinidine gluconate=IV. Combined with doxycycline or clindamycin to decrease the length of treatment.

Question 19

Quinine/Quinidine Gluconate toxicity

Answer 19

Cinchonism (tinnitus, HA, dizziness, flushing, visual distrubances), antiarrhythmis agent, QT prolongation, Hemolysis (G6PD deficiency)

Question 20

Doxycycline uses

Answer 20

combined with Quinine/Quinidine Gluconate to treat complicated choloroquine-resistant strains.

Question 21

Fansidar

Answer 21

pyrimethamine+sulfadoxine. Not available in the US

Question 22

Fansidar uses

Answer 22

presumptive treatment and acute attacks. especially used in affected areas for pregnant women and children.

Question 23

Malarone

Answer 23

atovaquone+proguanil. Synergistic combo effective in regions with high resistance

Question 24

Atovaquone MOA

Answer 24

Interferes with mitochondrial processes like the ETC/ATP and pyrimidine biosynthesis.

Question 25

Malarone uses

Answer 25

Active against blood and tissue forms.

Question 26

Artemisinin (Qinghaosu)

Answer 26

Most rapid action against falciparum. Not on US market.

Question 27

Artemeter/lumefantrine (Coartem)

Answer 27

Available in the US for cholorquine resistant falciparum and vivax

Question 28

Coartem toxicity

Answer 28

Prolonged QT (don't use in patients with cardiac disease).

Question 29

Primaquine

Answer 29

Only tissue schizonticide. Active against vivax and ovale for a radical cure.

Question 30

Primaquine contraindications

Answer 30

G6PD deficiency, SLE, RA, pregnancy (due to unknown fetal G6PD status)

Question 31

DOC for sensitive plasmodia

Answer 31

chloroquine or hydroxycholorquine

Question 32

DOC for cholorquine resistant falciparum

Answer 32

1. ) quinine with doxycycline or clindamycin 2. ) Mefloquine 3. ) Malarone 4. ) Coartem

Question 33

DOC for severe malaria

Answer 33

1. ) Quinidine with doxycycline or clindamycin | 2. ) Artemisinin combo therapy

Question 34

DOC for vivax or ovale

Answer 34

Always given primaquine to prevent relapse plus: 1. ) choroquine 2. ) quinine with doxycycline or clindamycin 3. ) Mefloquine 4. ) Malarone