anthelmintics.pptx.by dr dahad.pptxvvvvv

Abie

1. Anthelmintics 28 th Nov. 2011

2. Classification Nematodes Elongated round worms with complete digestive system (mouth & anus) Cause infections of intestine, blood & tissues E.g. Whip, thread, pin, hook Trematodes (Flukes) leaf-shaped flatworms. Characterized by the tissue they infest ( eg . Liver, lung, intestin , blood) Cestodes (True tape-worms) Flat, segmented body, attach to host’s intestine No GI/mouth

3. General Overview of Mechanisms Paralysis of the worm. D amaging the worm leading to partial digestion or rejection by immune mechanisms. Interfere with the metabolism of the worm.

4. Albendazole Mechanism Inhibits microtubule synthesis by binding to β – tubulin . Inhibits mitochondrial reductase causing reduced glucose transport. Intestinal parasites are immobilized and die slowly. Spectrum L arvicidal in hydatid disease ( Ehinococcus ) , cysticercosis ( Taenia solium : Neurocysticercosis ), ascariasis and hook worm infections. Ovicidal in ascariasis ,hookworm , trichuriasis DOC for hydatid disease and cysticercosis Ancylostomiasis & Strongyloidiasis cutaneous and visceral larva migrans , intestinal capillariasis , giardiasis & taeniasis

5. Pharmacokinetics & Side Effects Pharmacokinetics Administered orally , absorption increased with a fatty meal Metabolized in the liver to the active metabolite albendazole sulfoxide . t 1/2 =8-12 hours sulfoxide is mostly protein bound distributes well to tissues and enters bile,CSF & hydatid cysts. Metabolites are excreted in urine ADR In short term(1-3 days): Mild epigastric pain,diarrhea , nausea, headache & insomnia. In long term use : for hydatid cyst and cysticercosis : abdominal pain, headache ,fever ,fatigue, alopecia , increased liver enzymes , pancytopenia . Blood counts and liver enzymes should be followed. Not given during pregnancy, hypersensitive people to benzimidazole drugs & children under 2 years .