ID Lecture 46: Pharmacology of Antiparasitic Agents | Quizlet

What drugs treat amebiasis, giardia, and trichomoniasis?

Metronidazole

Nitazoxanide

Tinidazole

What drugs are used to treat pneumocystis?

Atovaquone

Pentamidine

Bactrim

What drugs are used to treat anthelmintics?

Albendazole

Mebendazole

Ivermectin

Praziquantel

Pyrantel pamoate

What drugs are used to treat malaria?

Artemesins

Lumefantrine

Atovaquone-proguanil

Chloroquine

Mefloquine

Pyrimethamine

Quinine

What drugs are used to treat scabies and lice?

Crotamiton

Lindane

Permethrin

Pyrethrin

Spinosad

Nitroimidazoles

Metronidazole

Tinidazole

Tinidazole

Nitroimidazole with a sulfoxide group

MOA of Metronidazole

prodrug, reductive activation of nitro group which binds to and causes DNA damage

Nitazoxanide MOA

prodrug; metabolically activated and then undergoes glucuronidation to act similarly to Metronidazole

ADRs of Nitazoxanide

Greenish urine discoloration

What is the drug of choice to treat Pneumocystis jirovecii (PJP)?

Bactrim

What is the second line treatment option for Pneumocystis jirovecii (PJP)?

Pentamidine

Atovaquone

Pentamidine MOA

fungicidal topoisomerase inhibition

Atovaquone MOA

inhibits the mitochondrial respiratory chain to irreversibly affect mitochondrial membrane potential

Quinine MOA

prevent conversion of hematin (toxic) to hemazoin (nontoxic)

ADRs of Quinine

Tinnitus

Visual disturbances

Premature contractions

Chloroquine MOA

synthetic derivative of quinine that prevent conversion of hematin (toxic) to hemazoin (nontoxic)

ADRs of Chloroquie

GI side effects

HA

Visual disturbances

Urticaria

Mefloquine MOA

similar action to chloroquines, but effective against many chloroquine-resistant strains

ADRs of Mefloquine

Neuropsychiatric

GI upset

Dermatological

Slow HR

Arrhythmias

Primaquine MOA

unclear BUT different than other quinolones becuase it is an 8-aminoquinolone (others have been 4-substituted)

Lumefantrine MOA

erythrocytic schizonticide that is used in combo with Artemether

ADRs of Lumefantrine

Anaphylaxis

HA

Dizziness

Anorexia

QT prolongation

Artemisinins MOA

endoperoxide group activation results in a carbon centered free radical mechanism in which the peroxide reacts with the iron in heme

ADRs of Artemisinins

Generally well tolerated

Pyrimethamine-Sulfadoxine MOA

combo DHPS and DHFR inhibitors to block parasite folate biosynthesis

Atovaquone-Proguanil MOA

-Atovaquone disrupts mitochondrial electron transport and DNA synthesis

-Proguanil (following activation) inhibits dihydrofolate reductase (antifolate mechanism) to inhibit DNA synthesis

Benzimidazoles

Mebendazole

Albendazole

Mebendazole MOA

inhibits fumarate reductase and binds to tubulin proteins to prevent tubulin polymerization to microtubules

Albendazole MOA

inhibits fumarate reductase and binds to tubulin proteins to prevent tubulin polymerization to microtubules

ADRs of Albendazole and Mebendazole

Gi upset

Liver dysfunction (long term use)

What are the contraindications of Albendazole and Mebendazole?

Pregnancy (teratogenic)

Ivermectin MOA

natural product that decreases the motility of helminths through chloride channel induction

Praziquantel MOA

Affects calcium distribution which leads to muscle contractions and expulsion

ADRs of Praziquantel

Diarrhea

Abdominal discomfort

Pyrantel Pamoate MOA

Depolarizing neuromuscular blocker, which causes paralysis of nematodes

What is the drug of choice for pinworms?

Pyrantel Pamoate

Malathion MOA

organophosphate that irreversibly inhibits cholinesterase

ADRs of Malathion

Skin and scalp irritation

Pyrethrum and Pyrethroids MOA

nerve membrane sodium channel toxin (prolongs opening)

Permethrin MOA

Inhibits sodium ion influx through nerve cell membrane channels in parasites resulting in delayed repolarization and thus paralysis and death of the pest

Lindane MOA

2nd line treatment for scabies that has insecticidal activity due to CNS stimulation due to GABA receptor antagonism

ADRs of Lindane

Potential systemic neurotoxicity

BBW of Lidnane

Avoid use in infants and individuals with known seizure disorders

Crotamiton MOA

2nd line treatment for scabies with an unknown mechanism

Spinosad MOA

ACh receptor agonist that results in CNS excitation, paralysis, and death of lice