Anti Parasitic drugs Flashcards
Inhibitors of parasite electron transport system
Atovaquone
Primaquine
Protozoal infections?
Plasmodium sp
Giardia lamblia
Entamoeba Histolytica
Toxoplasma Gondii
Inhibitors of Translation
bind to 30s or 50s ribosomal subunit to prevent parasite protein synthesis
Tetracycline
Doxcycline
Clindamycin
Inhibitors of Heme metabolism
results in build up of toxic heme metabolites which are lethal to the parasite Chloroquine Quinine, quinidine Mefloquine Artemisinins
Inhibitors of Folate metabolism
inhibits parasite nucleotide
Sulfadoxine plue pyrimethamine
Proguanil
pt has high fever, chills, severe headache, malaise and myalgia 4 days after returning from Nigeria. He took chloroquine prophylactically to prevent malaria. Blood smear shows banana shaped gametocytes. How should he be treated?
Artemisinin
Plasmodium Falciparum
What would you give for prevention of Malaria?
Remember to consider species and geographic region
Atovaquone/Proguanil
Chloroquine
Doxycycline
Mefloquine - worst side effects - crazy dreams
Primaquine
Sensitive (all four) strains of Plasmodium can be treated with?
Chloroquine or
Hydroxychloroquine
When treating P. vivax and ovale, you want to add?
Primaquine for the hypnozoites
Prescribe what for Chloroquine resistant P falciparum?
Atovoquone-proguanil
artemisinin
25yo medical student going on medical mission to Uganda, what should be given for prophylaxis?
All plasmodium species found here
Risk of malaria is High
Drug resistance to Chloroquine
Should give - Atovaquone-proguanil, doxycycline or mefloquine
33yo pt with high fever and chills. Returned from two month trip to India. Stopped prophylaxis (Atovaquone-proguanil)day before leaving India. Diagnosed with P. Vivax. Whats the treatement?
Chloroquine plus Primaquine
What are the drug options for Chloroquine resistant P. Falciparum?
Mefloquine
Quinine plus doxycycline or Clindamycin
Atovaquone plus proguanil (which is Malarone)
What can you give for chloroquine sensitive P falciparum and P malariae?
Chloroquine
P. Vivax and P. ovale infections, you would give?
chloroquine plus primaquine
12yo with 1 week of malaise, weakness, abdominal cramps and diarrhea. Pt is also bloated and has excessive flatulence. Stool is grey or light colored and greasy/fatty (steatorrhea) and not bloody. He has recently been camping and drink some of the stream water. what is the parasite? How would you treat it?
Giardia lamblia
Treat with Metronidazole, Nitazoxanide or Tinidazole
all three induce DNA damage and generate toxic radicals
what can be used for Entamoeba histolytica and Trichomonas vaginalis?
Metronidazole
Nitazoxanide
Tinidazole
An ultrasound is performed on pregnant woman in 24th week. Fetus shows hydrocephalis and intracranial calcifications. Mother was tested and found to have IgM antibodies to Toxoplasma gondii. What is the treatment?
Spiromycin - macrolide antibiotic - binds 50s ribosomes to block protein synthesis. This is DOC for this infection.
or
pyrimethamine/sulfadiazine (folate metabolism inhibitors) and D- Leucovorin (rescue antidote to prevent toxicity)
26yo volunteer returning from Kenya reports RUQ pain, abdominal pain, nausea, vomiting and diarrhea. Exam reveals Hepatosplenomegaly. Stool is positive for blood. Pt is dx with Schistosoma mansoni. Treatment?
Schistosomas are trematodes
would treat this with Praziquantel
what is the mechanism of Praziquantel?
used for tapeworm and trematode infections
Acts by increasing parasite membrane permeability to calcium. Results in parasite muscle contraction and paralysis
Childern in Peru village present with varying degrees of abdominal discomfort. Ova and parasite exam results from stool show Ascaris, Ancyclostoma and Trichuris. Treatment?
Albendazole, Mebendazole, Thiabendazole
How does Albendazole, Mebendazole and Thiabendazole work?
act by interfering with tubulin polymerizaiton leads to degradation of the integument
damages parasite intestinal epithelial cells
these are for treating nematode infections, cysticercosis (pig tapeworm in brain), echinococcosis
Pyrantel Pamoate
for round worms and hookworms
Acetylcholine agonist and depolarizing neuromuscular blocking agent
produces rigid contraction of nematode muscles
In village north of Cairo, WHO is attempting to reduce cases of lymphatic filariasis. What can cause this?
Wuchueria bancrofti
Brugia Malayi
What can cause SubQ filariasis?
Oncocerca volvulus
Loa Loa
How is Lymphatic and SubQ filariasis treated?
Ivermecitn
Diethylcarbamazine
Ivermectin
Microfilariae of Oncocera
binds with high affinity to glutamate gated chloride channels which occur in invertebrate nerve and muscle cells. Causes increase in permeability of cell membrane to chloride ions with hyperpolarization. Results in paralysis and death of parasite by causing worm to starve
Kills microfilariae slowly and thus prevent a host systemic immune response
Diethylcarbamazine
treat filarial worm infections
drug kills adult worms
Kills microfilariae quickly which can cause a systemic inflammatory response in pt with heavy microfilariae burden
acts by inhibiting microtubule polymerization in parasites
Treat Babesia microti with?
Clindamycin plus quinine
or
Atovaquone plus azithromycin
Treat toxoplasma gondii with?
spiromycin
Pyrimethamine/sulfadiazine and leucovorin
Treat Giardia lamblia with?
Metronidazole
Nitazoxanide
Tinidazole
Cestodes and Trematodes treatments?
Praziquantel
Albenazole
Nematodes
Albendazole, Mebendazole, Thiabendazole
Pyrantel pamoate
Ivermectin
Diethylcarbamzine
