Vomiting radiation-induced

Prevention of radiation-induced nausea and vomiting PO 2 mg once a day, given 1 hr before radiation therapy... 

Prevention of radiation-induced nausea and vomiting PO (Total body irradiation) 8 mg 1-2 hours daily before each fraction of radiotherapy. (Single high-dose radio-t herapy to abdomen) 8 mg 1-2 hours before irradiation, t hen 8 mg q8h after first dose for 1-2 days after completion of radiotherapy. (Daily fractionated radiotherapy to abdomen) 8 mg 1-2 hours before irradiation, then 8 mg 8 hours after first dose for each day of radiotherapy. 

Some trichothecene-induced effects may be due to neurotransmitter alteration in the central nervous system. Emesis or vomiting, which occurs with many of the trichothecenes when given at high doses, has been attributed to the stimulation of the chemoreceptor trigger zone in the area postrema of the medulla oblongata. However, studies with T-2 toxin in cats indicated that other mechanisms, such as the neural afferent pathways from the abdomen, implicated in radiation-induced emesis, may also be involved (Borison and Goodheart, 1989). DON alters serotonin activity in the central nervous system of swine which is important in... 

Patients receiving single-exposure, high-dose radiation therapy to the upper abdomen or receiving total or hemi-body irradiation should receive prophylactic antiemetics for radiation-induced nausea and vomiting (RINV). 

NVP nausea and vomiting of pregnancy PONV postoperative nausea and vomiting RINV radiation-induced nausea and vomiting SSRI selective serotonin receptor inhibitor... 

Radiation-induced emesis, or uncontrolled vomiting in patients undergoing radiation therapy, may necessitate either discontinuation of the treatment or prophylactic treatment with phenothiazine antiemetics. 

Indications Adults— used for prevention of chemotherapy-induced nausea and vomiting prevention of radiation-induced nausea and vomiting (oral only) postoperative nausea and vomiting (injection only). Pediatric (2 to 16 years)— used for prevention of chemotherapy-induced nausea and vomiting (injection only). Safety and efficacy are not established in patients younger than 2 years. 

The abdominal vagus and sympathetic nerves are the most important afferent inputs involved in vomiting induced by chemotherapy and radiation [31]. The input from vestibular nerves and the cerebellum plays an important role in the motion disease [52]. The afferent inputs from vagal, trigeminal and glossopharyngeal nerves terminate eventually in the nucleus solitarius tract located in the medulla oblongata which has neuronal connections with other medullary areas involved in emesis, for example, area postrema [53]. 

The severe nausea and vomiting induced by cytotoxic drugs and radiation in man can be reduced by metoclopramide given either atone or in combination with other drugs, such as dexamethasone. However, the extrapyramidal side-effects induced by metoclopramide, due to antagonism of dopamine re-... 

Unlabeled Uses Radiation therapy-induced nausea and vomiting... 

It causes antiemetic action by blocking dopamine (D receptors and it also increases gastric motility. It is absorbed orally but bioavailability is 15% due to first pass metabolism. It is completely biotransformed and metabolites are excreted in urine. It is used in nausea and vomiting in postoperative period, drug induced, radiation, uraemia, hepatitis, peptic ulcer. It is also useful in reflex oesophagitis. 

American Society of Health-System Pharmacists http //www.ashp.org Guidelines for managing postoperative and chemotherapy- and radiation-therapy-induced nausea and vomiting. 

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