Antiparasitic Drugs

Question 1

What are the four types of drugs to prevent malaria?

Answer 1

inhibitors of parasitic ETC, inhibitors of translation, inhibitors of heme metabolism, and inhibitors of folate metabolism

Question 2

What are the malaria ETC inhibitors?

Answer 2

Atovaquone, primaquine, and tafenoquine

Question 3

What are the malaria heme inhibitors?

Answer 3

Chloroquine, quinine, quinidine, mefloquine, artemisinins which all lead to build up of toxic heme metabolites which are lethal for parasite

Question 4

What are malaria inhibitors of translation?

Answer 4

tetracycline, doxycycline, and clindamycin all bind to 30 or 50S to prevent parasite protein synthesis

Question 5

Who can be negatively affected by malaria drugs?

Answer 5

People with G6PD deficiency

Question 6

How does plasmodium use hemoglobin as food source?

Answer 6

it detoxifies heme part to hemozoin which is what chloroquine inhibits

Question 7

What are forms of malaria chemoprophylaxis

Answer 7

chloroquine + primaquine = vivax + ovale
mefloquine, doxycycline, atovaquone+proguanil = p. falciparum

Question 8

Which drugs are active against dormant forms of plasmodium malaria? What are those dormant forms called?

Answer 8

Primaquine and tafenoquine are active against dormant hypnozoites in the liver and prevent relapse.

Question 9

How’s malaria treated?

Answer 9

Chloroquine resistant Plasmodium = artemisinin, mefloquine, quinine + doxy or clindamycin, or atovaquone + proguanil
Chloroquine sensitive p falciparum = chloroquine
P. vivax and ovale = chloroquine + primaquine or tefenoquine

Question 10

How do you treat Giardia lamblia?

Answer 10

metronidazole, nitrazoxanide, tinidazole

Question 11

Which parasites can be treated with Metronidazole?

Answer 11

Giardia lamblia, Entamoeba histolytica, trichomonas vaginalis

Question 12

What do you treat toxoplasma gondii with?

Answer 12

Remember that this can cross placenta! So for the fetus, treat with pyrimethamine/sulfadiazine (folate metabolism inhibitors) with leucovorin which prevents toxicity of folate inhibitors.
Adults get spiromycin - macrolide

Question 13

What are symptoms of schistosoma mansoni (trematode) and what do you treat it with?

Answer 13

RUQ pain, hepatosplenomegaly, abdominal pain, nausea, vomiting, and diarrhea, which you treat with Praziquantel

Question 14

What is mechanism of action for praziquantel?

Answer 14

used for tapeworm and trematode infections and acts by increasing parasite membrane permeability to calcium causing paralysis.

Question 15

What do you treat Ascaris, Ancyclostoma, and Trichuris with?

Answer 15

Albendazole, Mebendazole, and Thiabendazole

Question 16

What’s mechanism of action of Albendazole, Mebendazole, and Thiabendazole?

Answer 16

they interfere with tubulin polymerization, which prevents microtubules in glucose uptake and cell replication. Use on nematodes cysticercosis, and echinococcosis

Question 17

This drug works on round worms and hook worms?

Answer 17

Pyrantel Pamoate

Question 18

This drug is an acetylcholine agonist and blocks depolarization causing nematode muscle rigidity?

Answer 18

Pyrantel Pamoate

Question 19

Which organisms cause lymphatic filariasis?

Answer 19

Wuchueria bancrofti and Brugia malayi

Question 20

Which organisms cause subcutaneous filariasis?

Answer 20

Onocerca volvulus and Loa loa

Question 21

What do you treat filariasis infections with?

Answer 21

Ivermectin and Diethylcarbamazine

Question 22

What is the mechanism of action of Ivermectin?

Answer 22

Binds to high affinity to glutamate gated Cl channels of Onocerca causing increase in the permeability of cell membrane to Cl. Hyperpolarization results in paralysis and death of parasite. Kills slowly so no inflammation

Question 23

What is mechanism of action Diethylcarbamazine?

Answer 23

Treats Loiasis. Unlike ivermectin this drug kills adult worms. Also killd microfilariae causing inflammation. Rapid killing can lead to blindness.

Question 24

How do you treat pediculus humanus corporis, pediculus humanus corporis, and Pthirus pubis?

Answer 24

You treat with OTC insecticides: Pyrehtrins + piperonyl butoxid