Antiparasitic Agents

Front 1

Antimalarial: Cholorquine

Back 1

1. TX: blood stages of P. malariae, ovale, vivax, and some falciparum. large ring and mature trophozoite stages. may be used during pregnancy

2. MECHANISM: disrupts hemoglobin digestion in parasitic food vacuoles

3. RESISTANCE: interference with accumulation (efflux pumps?)

4. ADVERSE: HA, GI, pruritus, visual problems

Front 2

Antimalarial: Mefloquine

Back 2

1. TX: MDR P. falciparum. prevention and oral tx for uncomplicated malaria. may be used in pregnancy

2. MECHANISM: high VD, long t1/2, interacts with food vacuoles.

3. CLEARANCE: highly bound, hepatic biotransformation (inactive metabolites)

4. ADVERSE: GI, HA, insomnia, abnormal dreams, neuropsych

5. CONTRAINDICATIONS: psychiatric illness, cardiac conduction abnormalities, sz disorders

Front 3

Antimalarial: Atovaquone (Malarone)

Back 3

1. TX: borad spectrum antiprotozoal activity. active against erythrocytic and exoerythrocytic forms of P. falciparum and P. vivax. used in prevention (daily dose) and tx

2. MECHANISM: inhibits electron transport, highly lipophilic, long half life, poor CNS

3. used in combination with proguanil (Malarone)

Front 4

Antimalarial: Proguanil (Malarone)

Back 4

1. TX: schizonticidal activity against all erythrocytic forms. active against sporozoites and hepatic forms of P. falciparum

2. MECHANISM: inhibits DHR. Folate antagonist. short t1/2, poor absorption

3. used in combo with atovaquone (Malarone) in prevention (daily dose) and tx

Front 5

Antimalarial: Primaquine

Back 5

1. TX: schizonticidal. active against exoerythrocytic forms (P vivax and ovale) and gametocytes. radical cure for the above

2. contraindicated in G6PD deficiency. last line

Front 6

Antimalarial: doxycycline

Back 6

1. protein synthesis inhibitor

Front 7

Antimalarial: Quinine/ quinidine

Back 7

1. TX: cinchona alkaloids used for tx of severe malaria. quinidine (PO) for uncomplicated cases

2. high toxicity

Front 8

Antimalarial: artesunate

Back 8

1. TX: severe malaria. PO form for uncomplicated cases. combo of artemether and lumefantrine

2. ADVERSE:
-HA, anoreixa, dizziness, asthenia, arthralgia, myalgia, in kids, fever, cough, vomit, anorexia, HA
- Lumefantrine associated with prolonged QT, so should be aboided with halofantrine and quinine

Front 9

tx for luminal protozoa: Metronidazole

Back 9

1. TX: active against protozoa, invasive amebiasis, giardiasis, trichominiasis, and bacterial infections (anaerobes). used in pregnancy after 1st trimester

2. MECHANISM- damages DNA. PO/IV. metabolized in liver

3. ADVERSE: GI, dysgeusia (decrease/ distortion of taste), dizziness, disulfiram rxn, potenitate warfarin

Front 10

tx for luminal protozoa: Tinidazole

Back 10

1. TX: similar to metronidazole

2. longer t1/2, and fewer side effects

Front 11

tx for luminal protozoa: Paramomycin

Back 11

- aminoglycoside
- PO, poor absorption
- GI effects, oto/nephrotoxic effects

Front 12

tx for luminal protozoa: Nitazoxanide (Alinia)

Back 12

- thiazolide
- tx for diarrhea
- good oral absorption
- broad antiprotozoal and antihelminthic activity
- mild side effects

Front 13

tx for helminths: Benzimidazole

Back 13

- broad spectrum antihelminthic
- inhibition of microtubule polymerization
- active against larvae, adults, some eggs
- not used in pregnancy

Front 14

tx for helminths: Albendazole

Back 14

- oral absorption given with fatty meal
- rapid hepatic metabolism. excreted in urine
- low toxicity

Front 15

tx for helminths:Mebendazole

Back 15

- poor oral absorption
- rapid first pass
- low toxicity
- GI nematodes

Front 16

tx for helminths: Ivermectin

Back 16

- macrocytic lactone
- tx for nematodes and ectoparasites (strongyloides, onchocerciasis, scabies)
- tonic paralysis of parasitic musculature
- good oral, long t1/2
- low toxicity, but may have adverse rxn to parasitic antigens
- safe in pregnancy?

Front 17

tx for trematodes (flukes) and cestodes (flatworms): Praziquantel

Back 17

- inc membrane permeability to cations. causes spastic paralysis (low dose) and tegument damage (high dose)
- good oral
- metabolized in liver
- GI side effects
- safe in pregnancy
- tx: Schistosoma spp., cestodes (tapeworms), and most trematodes