5 Written Questions

1. -antihelminthics
   -not effectivly absorbed, treat luminal nematodes
   -GI toxicity
   -contrindicated durng pregancy
   -spectrum: ASCARIASIS, PINWORM, HOOKWORM, WHIPWORM
2. -abendazole, mebendazole, thaibendazole
   -MOA: inhibit mitosis in the parasite
   CONTRAINDICATED IN PREGNANCY AND CHILDREN UNDR 2
3. -inhibitors of enzyme DHFR
   -basis for selective toxicity (parasite DHFR is inhibited at considerably lower concentrations of drug than the mammalian DHFR)
4. -MOA: increase the Ca++ permeability of the worm's tegument causing its depolarization, induce spastic paralysis
   spectrum: drug of choice for treating nearly all infections of man cause by tapeworms and flukes
   FLUKES: THREE DOSES IN A SINGLE DAY
   TAPEWORMS: A SINGLE DOSE
   CYSTICERCOSIS: TWO WEEKS TREATMENT
5. -PABA analogs that block dihydropteroate synthase

5 Matching Questions

1. trimethoprim-sulfamethoxazole
2. paromomycin
3. thiabendazole
4. ivermectin
5. nitazoxanide

1. a -treats Cryptosporiosis (seen basically in just AIDS)
   MOA: interferes with PF oxidoreductase
   -spectrum: cryptosporidiosis and giardiasis
   crypto: profuse watery diarrhea
2. b -antihelminthic
   -better absorption
   -toxicity: GI, CNS
   -contraindicated in pregnancy
   -spectrum: second line in STRONGYLOIDAISIS, topical used IN CUTANEOUS LARVAL MIGRANS
3. c -treats Pneumocystis jirovecii
   MOA: inhibits folate synthesis (we can scavenge folate from our diet, protozoa cannot)
   -use higher doses to treat active disease
   -lower doses used for life-long maintenance
   -resistance widely reported, point mutations on targeted enzyms
4. d -MOA: hyperpolarization in muscle cells, resulting in paralysis of helminth, no effect on mammailian cells
   -drug of choice for treating STRONGYLOIDAISIS
5. e -aminoglycoside antibiotic (inhibits protein synthesis in bacteria)
   -MOA on E. histolytica is unknown
   -effective at eliminating trophozoite and cyst forms of E. histolytica from the LUMEN of the intestine (poorly absorbed)
   -safer than similar drug
   -used to treat asymptmatic or mild cases of amebiasis
   SEVERE CASES: should FOLLOW metronidazole

5 Multiple Choice Questions

1. -treats toxoplasma gondii
   MOA: inhibits folate synthesis (we can scavenge folate from our diet, protozoa cannot)
   -use higher doses to treat active disease
   -lower doses used for life-long maintenance
   -resistance widely reported, point mutations on targeted enzyms
   1. primaquine
   2. pyrimethamine-sulfadiazine
   3. trimethoprim-sulfamethoxazole
   4. metronidazole
2. MOA: ?
   -effective at eliminatingtrophozoite and cyst forms of E. histolytica from the LUMEN on the intestine (poorly absorbed)
   -children + high doses + prolonged periods = optic atrophy and permanent vision loss
   -used to treat asymptmatic or mild cases of amebiasis
   SEVERE CASES: should FOLLOW metronidazole
   1. mefloquine
   2. iodoquinol
   3. chloroquine
   4. quinine
3. -treats Giardia, Entamoeba, Trichomonas: all of which are ANAEROBIC lumen dwelling
   -all of the organisms possess PF oxidoreductase (we do not have this enzyme)
   -drug is an electron "sink"
   -enters cell in inactive form, is activated by PFOR --REACTIVE INTEMEDIATES DISRUPT PROTEIN AND DNA STRUCTURE
   -adverse: disulfram like -- avoid alcohol consumption
   -Amebiasis: DRUG OF CHOICE FOR SYMPTOMATIC , NEEDS TO BE FOLLOWED WITH A MORE POTENT LUMINAL AMEBICIDE TO ERADICATE NON-INVASIVE CYST FORMS
   resistnce: rare
   1. thiabendazole
   2. BENZIMIDAZOLES
   3. malarone
   4. metronidazole
4. -tetracycline used for malaria prophylaxi and treatment
   -MOA: disrupts protein synthesis of plasmodium
   -adverse: photosensitivity, stain teeth (contraindicated in preggos and children)
   -spectrum: all species of plasmodium
   1. quinine
   2. chloroquine
   3. doxycycline
   4. mefloquine
5. -MOA: activates cholinergic nicotinic receptors in somatic muscles of nematodes and thereby produce a depolarizing neuromuscular blockade ( no effect on humans)
   -poorly absorbed (selective for intestinal nematodes)
   -mild GI disturbances
   -spectrum: drug of choice for PINWORM, ENTIRE HOUSEHOLD MUST BE TREATED
   1. pyrantel pamoate
   2. praziquantel
   3. thiabendazole
   4. malarone

5 True/False Questions

1. chloroquine → -antmalarial
   -MOA: ? simiar to quinine
   -**used for prophylaxis (weekly) and treatment
   -adverse: neuropsychiatric reactions
   -spectrum: effective against all species of plasmodium

   True        False

2. mefloquine → -antmalarial
   -MOA: ? simiar to quinine
   -**used for prophylaxis (weekly) and treatment
   -adverse: neuropsychiatric reactions
   -spectrum: effective against all species of plasmodium

   True        False

3. primaquine → -antmalarial
   -MOA: ? simiar to quinine
   -**used for prophylaxis (weekly) and treatment
   -adverse: neuropsychiatric reactions
   -spectrum: effective against all species of plasmodium

   True        False

4. quinine → -antimalarial
   -MOA: may interfere with hemoglobin degredation, ma complex with parasite DNA, interfering with transcription and replication
   **poorest therapeutic: toxic ratio of all antimalarial drugs
   -adverse: cinchonism, hypoglycemia
   -not used for prophylaxis due to its toxicity
   -spectrum: eliminates asexual erythrocytic stages of all species of plasmodium
   -resistance: beginning to emerge

   True        False

5. malarone → -antimalarial
   -combination of atovaquone and proguanil
   -highly efficaciou in the treatment of P. falciparum malaria, as well as in prophylaxis
   -atovaquone:: MOA: unknown, poorly absorbed by itself, shown to have activity against all species of Plasmodium
   -proguanil: inhibits DHFR

   True        False