Vomiting antiemetics

Apomorphine is approved for acute off episodes in patients with advanced stages of PD. The onset of effect is within 10 to 20 minutes and the duration of effect is about 60 minutes. It requires premedication with an antiemetic because it causes nausea and vomiting. Antiemetics that block central dopamine worsen the symptoms of PD, and 5-HT3 antagonists, such as ondansetron, can aggravate PD-related hypotension. Trimethobenzamide (300 mg three times daily) should be... 

Prevent postsurgical nausea and vomiting (antiemetic drug)... 

Ondansetron Alcohol Ondansetron is a serotonin 5-HT3 receptor antagonist, with low affinity for al-adrenergic, 5-HTiB, 5-HTiC, and J-opioid receptors [251]. It is used primarily to treat nausea and vomiting (antiemetic) following chemotherapy. 

Antiemetic. A compound that blocks the vomition reflex. 

Opioids act on the area postrema and/or the NTS via p or 8 receptors to produce emesis. Also, ambulatory patients receiving opioids are more affected than those confined to bed, suggesting a vestibular component in the effect. The emetic action of opioids is complicated by an antiemetic action, possibly involving two receptors at the NTS or the vomiting centre. 

Dronabinol (tetrahydrocannabinol), the active principle from cannabis and synthetic cannabinoids, nabilone and levonantradol are effective in treating nausea and vomiting in cancer chemotherapy. The mode of action is unclear but appears to involve cannabinoid CBi receptors. Cannabinoids have been shown to reduce acetylcholine release in the cortex and hippocampus, and have been suggested to inhibit medullary activity by a cortical action. Inhibition of prostaglandin synthesis and release of endorphins may also be involved in the antiemetic effect. A review of trials of dronabinol, nabilone or levonantradol concluded that while the cannabinoids were superior to placebo or dopamine receptor antagonists in controlling emesis... 

It is important to note diat antivertigo dragp are essentially antiemetics because many of these preparations, whedier used for motion sickness or vertigo, also have direct or indirect antiemetic properties. They prevent the nausea and vomiting diat occur because of stimulation of die vestibular apparatus in the ear. Stimulation of diis apparatus results in vertigo, which is often followed by nausea and vomiting. 

Antiemetic—to lessen the incidence of nausea and vomiting during the immediate postoperative recovery period. 

Antineoplastic drugs are potentially toxic and their administration is often associated with many serious adverse reactions. At times, some of these adverse effects are allowed because the only alternative is to stop treatment of the malignancy. A treatment plan is developed that will prevent, lessen, or treat most or all of the symptoms of a specific adverse reaction. An example of prevention is giving an antiemetic before administering an antineoplastic drug known to cause severe nausea and vomiting. An example of treatment of the symptoms of an adverse reaction is the administration of an antiemetic and intravenous (IV) fluids and electrolytes when severe vomiting occurs. 

Standardised preparations of cannabinoid agonists are available for therapeutic use in some countries [238]. Dronabinol (Marinol ), an oral preparation of A -THC (67), is used clinically as an appetite stimulant in AIDS patients and an antiemetic in cancer chemotherapy. A synthetic analogue of (67), nabilone (Cesamet ), (381), is also used to suppress nausea and vomiting in cancer chemotherapy. 

Profuse or prolonged vomiting can lead to complications of dehydration and metabolic abnormalities. Patients must have adequate hydration and electrolyte replacement orally (if tolerated) or intravenously to prevent and correct these problems. Some pharmacologic treatments work locally in the GI tract (e.g., antacids and prokinetic agents), whereas others work in the central nervous system (e.g., antihistamines and antiemetics).1... 

Stimulation of dopamine (D2) receptors in the CTZ leads to nausea and vomiting (Fig. 17-1). Phenothiazine antiemetics... 

Gan TJ, Meyer T, Apfel CC, et al. Consensus guidelines for managing postoperative nausea and vomiting. Anesth Analg 2003 97 62-71. Gralla RJ, Osoba D, Kris MG, et al. Recommendations for the use of antiemetics evidence based clinical practice guidelines. J Clin Oncol 1999 17 2971-2994. 

Hydration, heating pads, relaxation, and distraction Stool softener and/or stimulants for constipation Antihistamine for itching Antiemetics for nausea or vomiting... 

A second current clinical indication of cannabimimetics is their antiemetic and antinausea effects, especially in cancer chemotherapy patients. These effects are mediated above the level of vomiting reflex and possibly through descending inhibitory connections to the lower brain stem centers (Levitt, 1986). 

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