Antiparasitic Chemotherapy Flashcards
Why is it harder to treat parasitic infections than bacterial?
Limited targets for Antiparasitic drugs.
What are the 3 targets for antiparasitic chemotherapy?
- Ez processes only in parasities
- Ez in Host and parasite but vital only in parasite
- Commonbiochemical functions in para and host but different Pharm Properties.
What drug Can treat Giardia, Amebiasis, and Trichomoniasis?
Metronidozol
What are examples of Parasitic Intestinal and Luminal infections that are treated by Metronidozol?
Giardia, Amebiasis, and Trichomoniasis
Which 2 intestinal parasites have 2 forms?
Entamoeba and Giardia
What Ez in parasites allows them to be anaerobic?
PFOR(Pyruvate; ferrodoxin oxidoreductase)
How do parasites activate Metronidozol?
PFOR Reduces and radicalizes the drug after which it can do damage. It diverts electrons from the normal Energy yielding pathways.
What are side effects of Metronidozol?
Metallic Taste. Makes them vomit after drinking alcohol.
How is Metronidazol given in Trichomoniasis?
Topical or Vaginal Suppository if oral doesn’t work. Sexual partners need simultaneous treatment!
What needs to be given after Metronidozol treatment in Amebiasis?
A more potent luminal ameobocide! Eradicate non invasve cyst forms.
What is the drug used for E. Histolytica?
Iodoquinol. Doesn’t affect trophozoite forms. Follow with Paromycin to kill cysts and trophozoite from Lumen of the intestine.
Wahat are the limitations of Paramomycin?
Doesn’t treat orgamnisms that have invaded tissue!
What is the Treatment for Cryptosporidiosis?
Nitazoxanide. Interferes with PFOR.
Which Parasites can be treated by Folate synthesis pathway?
Pneumocystic Jirovecii
Toxoplasma gondii
Which Drugs are Folate Synth Inhibitors?
TMP-SMX
Pyrimethamine-Sulfadiazine
What enzyme do Diaminopyrimidines inhibit?
DHFR. Prevents THF formation
What enzyme do Sulfonamides inhibit?
Dihydropterate synthase.
no conversion of PABA to pteroic acid.
What are the adverse effects from Sulfonamides?
Rash, Crystaluria, Gi intolerance, and Hemolysis.
What drugs treat toxoplasmosis?
Pyrimethamine-sulfadiazine
Waht are the considerations for using Chloroquine?
Oral admin, half life of 4 days, SA of headache, nausea, vomiting and blurred vision.
What are Toxic effects of Mefloquine?
Rare neuropsychiatric reactions. Hallucinations, etc but are rare.
What drug has effects against hypnozoite forms of P. vivax and P. ovale in the liver.
Primaquine
What screening has to be done before giving Primaquine?
G6PD deficiency. otherwise you’ll get RBC lysis of RBCs
What combo of drugs constitutes Malarone? and what does it treat?
Atoviquone and proguanil.
P. Falciparum
What are dietary considerations in Atoviquone
Eat with fatty meal. poorly absorbed but is lipid soluable.
How does Proguanil work?
Inhibits DHFR
How does Doxycycline work?
Inhibits growth of Plasmodium by disrupting protein synthesis.
Side effects of Doxycycline?
Photosensitivity Dermatitis. and teeth staining in children.
Which drug is an extract of Chinese Wormwood?
Artemensin
diaetary considerations for Benzimidazoles.
Poorly absorbed. Eat on an empty stomach to keep it in the intestines.
Side effects of benzimidazoles?
GI and CNS Disturbances.
DO NOT use during pregnancy.
What is used to treat strongyloidiasis and cutaneous larval migrans?
Ivermectin 1st and Thiabendizole 2nd. Better tissue penetration.
What is MOA of antihelminthics?
Paralyzes the worms and they are pooped out.
Waht is the treatment for Pinworms?
Pyrantel Pamoate. Treat the WHOLE HOUSEHOLD!
What is the MOA of Praziquantel?
Increases Ca2+ permiability of worm’s tegument-> paralysis, increases detection and decreases defense against immune cells.
