Antiprotozoal Agents Flashcards Preview

RRPA Pharmacology II > Antiprotozoal Agents > Flashcards

Flashcards in Antiprotozoal Agents Deck (25)
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1

These parasitic infectious organisms can all be treated with what?
-Amebiasis (Entamoeba histolytica
-Trichomoniasis (T. vaginalis)
-Giardiasis (Giardia lamblia)

Metronidazole

2

What is the name for worm diseases?

Helminthic

3

These worms can all be treated with what agent?
-Hookworm (Necator americanus)
-Roundworm (Ascariasis)
-Pinworm (Enterobiasis)

Albendazole

4

Hookworm (Necator americanus) is found where in the US?

Southeastern US

5

Roundworm (Ascariasis) is found where in the US?

Appalachia
Gulf Coast

6

Pinworm has the most cases out of the three worms French presented to us at how many million? Cases mostly seen in which population?

42 million
Children
** Can be treated with albendazole but ALSO Pyrantel

7

Malaria can infect which two areas of the body? Which has higher mortality?

Blood (erythrocytic) = P. falciparum
Liver (exoerythrocytic) = P. vivax, P. ovale

*Blood has highest mortality, responsible for 85% of deaths

8

What is important to consider when treating malaria?

Resistance patterns of geographic regions

*P. falciparum (blood) chloroquine resistance becoming more prevalent

9

What is the vector for malaria?

Plasmodium-infected mosquitos

10

You have a pt traveling to Mexico-Caribbean and wants PROPHYLAXIS tx for malaria. What should you know about this area and what is the tx?

Mexico/Caribbean is chloroquine SENSITIVE

Tx: chloroquine 1-2 wks prior to travel and 4 wks after

11

You have a pt traveling to South America (South Africa and Asia to be specific) and wants PROPHYLAXIS tx for malaria. What should you know about this area and what is the tx?

South Americas (South Africa and Asia) are chloroquine RESISTANT

Tx: Atovaquone/proguanil daily 1-2 days prior travel and 1 wk after

Doxycycline: daily 1-2 days prior and 4 wks after

Mefloquine: Weekly 1-2 wks prior and 4 wks after

12

Tx for non-falciparum (i.e. P. ovale and P. vivax)

Tx (acute): Chloroquine

Tx (resistant): Mefloquine or atovaquone-proguanil or quinine + doxycycline

*Liver form (aka hypnozoite) to prevent relapse = Primaquine

13

Tx for P. falciparum?

Artemisinin combinations PLUS mefloquine OR sulfadoxine-pyrimethamine

OR

atovaquone-proguanil OR quinine + doxycycline or clindamycin

*Don't forget P. falciparum has widespread chloroquine resistance

14

Tx for SEVERE P. falciparum?

artemisinin IV OR quinine/quinidine IV + antimicrobial

15

What is the mechanism of action (MOA) of chloroquine?

Interferes with feeding mechanism of parasite by raising blood pH (alkaline).

*Selective toxicity depends on drug concentration in parasite (25X plasma level)

16

How is chloroquine absorbed and what would you tell your pts to avoid while dosing?

Rapid and complete oral absorption

Tell pts to avoid antacids as it hinders absorption

17

Where does chloroquine concentrate in the body?

Liver and kidneys, has large Vd (volume distribution) therefore needs LOADING DOSE

18

What method of administration do you NOT give chloroquine?

IM = hypotension, shock, sudden death

*high total doses over 100 grams = ototoxicity, myopathy and IRREVERSIBLE retinopathy

*Children especially sensitive to toxicities

19

Mefloquine is related to quinine and is less toxic, but was given a black box warning in 2013 which contraindicates use for who?

Pts w/ neurologic and psychiatric disorders
Also pts with heart conduction abnormalities

20

Of the quinolines which is the most toxic?

Quinine = narrow therapeutic window
-given parenterally for acute infection
-overdose = cardiotoxicity, blindness and deafness

21

Of the quinolines which is the least toxic?

Primaquine. It is also the most effective antimalarial

Good for radical cure (liver stages)

22

Who would you avoid giving primaquine to? Think of blood disorders.

G6PD deficiency = hemolysis
contraindicated in pregnancy

23

What is the MOA of primaquine?

Drug metabolites act as oxidants via unknown mechanism

24

What is the drug of choice for severe falciparum malarial infection?

artesunate IV (most rapid and potent onset)

Artemether PO after above therapy

25

What are some ADRs of artesunate? What do you monitor pts for after tx?

2-9% = acute renal failure, sepsis, coma, seizure, shock, respiratory failure

Monitor for 4 wks for possible severe post-tx hemolytic anemia