Antiprotozoal drugs

Question 1

Chagas disease specific drugs

Answer 1

Nifurtimox

Ni Fur Ti Mox
and
Benznidazole

Only slows progression, not curative or halting, most effective in the acute phase.

SEs:
GI 
Neuropathic
Insomania
Seizures

Question 2

What are the trypanosomes

Answer 2

Bruci and Cruzi

Trypanosomas brucei gambiense and rhodesiense
cause sleeping sickness

and
Trypanosomas cruzi -
causes chagas disease

Question 3

Drugs for trypanosomiasis without CNS involvment

Answer 3

Suramin
Pentamidine

Pentamidine - also a blood schizonticide for vivax and ovale malria.

Question 4

Mechanism of the nitroimidazole class.

Answer 4

Metronidazole is of the nitroimidazole class. It inhibits nucleic acid synthesis by disrupting the DNA of microbial cells.[1] This function only occurs when metronidazole is partially reduced, and because this reduction usually happens only in anaerobic cells,

Question 5

Drugs for Trypanosomiasis with CNS infection

Answer 5

Melarsoprol - arsenic based drug with high toxicity. Only for advanced trypanosomiasis.

many side effects, including cerebral edema, seizures, coma, and death.

Eflornithine - Inhibits Ornithine Decarboxylase.
Also many SEs,
Seizures
Thrombocytopenia and Leukocytopenia.

Question 6

Drugs for Leishmania

Answer 6

For visceral leishmaniasis: Amphotericin B.

For Mucocutaneous form:

Sodium Stibogluconate
Miltefosine
few side effects

Pentamidine: reserved for resistant cases. Unclear mechanism. 
Parenteral administration.
Severe SEs.
Stevens-Johnson syndrome
Arrythmias
Liver and kidney toxicity.

Question 7

Drugs for tissue amoebiasis:

Answer 7

Metronidazol
Tinidazol
Ornidazol
Produce cytotoxic products in the presence of anaerobic metabolism.

Nitazoxanide: Broad spectrum anti-protozoal drug, unknown mechanism. low side effects.

Emetine
Derived from the Emetic Ipecac. inhibit protein and DNA synthesis.

Paramycin
Aminoglycoside that inhibits the 30S ribosomal prokaryotic subunit. 2nd line for extraintestinal infecitons.

Question 8

Drugs for intestinal ameobiasis

Answer 8

Paramycin - aminoglycoside
Diloxanide - unclear mechanism
Idoquinol - unclear mechanism

Have poor absorption and thus high action in the intestine.

Question 9

name some amoeba infections

Answer 9

Giardia lamblia
Entamoeba histiolytica.
Trichomonas vaginallis

Question 10

Metronidazole side effects

Answer 10

The Disulfuram like reacion with alcohol
Immediate hangover, vomiting nausea
Tachycardia and palpitations
Metallic taste

Question 11

Giardia drugs

Answer 11

Metronidazole, Tinidazole

Nitazoxanide

2nd line: paramycin

Question 12

Trichomonas vaginalis drugs

Answer 12

Nitroimidazoles

Metronidazole and Tinidazole

Question 13

Toxoplasma gondii drugs

Answer 13

Spiramycin for preggos.

DoC: Sulfamethoxazole and Trimethoprim.

Question 14

Pneumocystis jiroveci drugs

Answer 14

Sulfamethoxazole and Trimethoprim

Question 15

Side effects of Sulfamethoxazole and Trimethoprim

Answer 15

The combination potently inhibits the generation of tetrahydrofolate. Sulfonamides -( dihydrofolate synthesis, Trimethoprim -( Dihydrofolate reductase and Tetrahydrofolate synthesis.

Skin rash, potentially lethal Stevens Johnson syndrome
Toxic Edpidermal Necrosis

Thrombocytopenia (no THF, no replicating cells)
Leukocytopenia

Hepatitis
Hyperkalemia

Question 16

Antihelmithic drugs, just list them

Answer 16

nematodes - roundworms
trematodes - flukes
cestodes - tapeworms

Benzimidazoles
Ivermectin
Praziquantel
Levamisol
Niclosamide
Pyrantel Pamoate
Bithionol

Question 17

Benzimidazoles, drugs and mechanism

Targets

Answer 17

Albendazole, Mebendazole, Tiabendazole
Inhibits tubulin polymerization of the worms.
Paralysis and death.

Roundworms and Tapeworms. Nematodes and Cestodes.

Extra-intestinal helminth treatment.

Question 18

Benzimidazoles SEs

Answer 18

GI
Hepatotoxic
Visual disturbance
Teratogenic

Question 19

Ivermectin mechanism, targets, distribution

SEs

Answer 19

Mechanism: enhances GABA signaling in the worms, paralysis

Oral admin and does not cross the BBB

minimal/no SEs, are only due to inflammation from the worms dying and causing inflammation.

targets: Roundworms. Filariasis, Ascaris lumbricoides, Ancylostoma duodenale, Tricuris trichuria (pinworms)

Question 20

Niclosamide

mechanism, targets, SE

Answer 20

Inhibits oxidative phosphoylation of Tapeworms

Poor absorption, given orally to work in the intestine. Niclosamide iNtestinal
thus, SEs are mild and essentially just intestinal too.

Targets: Taenia solium and saginata.

Question 21

Pyrantel Pamoate

mechanism, targets, SE

Answer 21

Inhibits worm AChE and stimulates acetylcholine release.
Depolarizing paralysis.
Orally and poor absorption.
Significant GI side effects and moderate CNS ones.

Axcaris, Necator, Ancylostoma, Enterobius.

Question 22

Praziquantel

Answer 22

Increases Ca++ permeability of the worm and causes spastic paralysis.

Oral, good absorption and CNS penetration.

SEs:
GI and Dizziness.

Given against flukes and tapeworms.

Question 23

Levamisol

Answer 23

Depolarizing blockade and paralysis
Oral
GI side effects, mild neurological effects.

Good for roundworms, ascaris lumbricoides, Necator Americanus
Ancylostoma duodenale

Question 24

Bithionol

Answer 24

Inhibits oxidative phosphorylation, like niclosamide,
but its for Flukes instead of tapeworms.
Specifically its for
Fasciola hepatica, liver fluke.

Its main SE is also Toxic Hepatitis
as well as GI and CNS effects, dizziness, headache.