A 56-year-old woman has nausea due to chemotherapy for breast cancer. Droperidol is effective in reducing nausea because it blocks wof
NEUROLEPTICS The older neuroleptics(phenothiazines, haloperidol) are potent antiemetics; act by blocking D2 receptors in the CTZ; antagonize apomorphine induced vomiting and have additional antimuscarinic as well as H1 antihistaminic propey. They have broad spectrum antiemetic action effective in: (a) Drug induced and postoperative nausea and vomiting (PONV). (b) Disease induced vomiting: gastroenteritis, uraemia, liver disease, migraine, etc. (c) Malignancy associated and cancer chemotherapy (mildly emetogenic) induced vomiting. (d) Radiation sickness vomiting (less effective). (e) Morning sickness: should not be used except in hyperemesis gravidarum. Ref:- kd tripathi; pg num:-664
5-HT 2 receptors in the CTZ
Glucocoicoid receptors in the vomiting center
Dopamine receptors in the CTZ
ACh receptors in the periphery
Gastrointestinal tract