Benzodiazepines vomiting

Benzodiazepines, especially lorazepam, are used to prevent and treat CINV.5,10 Lorazepam is thought to prevent input from the cerebral cortex and limbic system from reaching the central vomiting center in the brain stem.10 Sedation and amnesia are common side effects. Respiratory depression can occur with high doses or when other central depressants such as alcohol are combined with benzodiazepines. 

Moderate, high, and very high likelihood of nausea/vomiting—5-HT3 antagonist (as above) and dexamethasone (as above) benzodiazepine Low likelihood of nausea/vomiting—Compazine Very low likelihood of nausea/vomiting—Compazine only if needed ... 

Numerous neurotransmitter receptors are located in the vomiting center, CTZ, and GI tract. Examples of such receptors include cholinergic and histaminic, dopaminergic, opiate, serotonin, neurokinin (NK), and benzodiazepine receptors. Theoretically, chemotherapeutic agents, their metabolites, or other emetic compounds trigger the process of emesis through stimulation of one or more of these receptors. 

In anesthesia drugs from several groups are used as premedication. Pre-anesthetic medication can decrease the anesthetic doses which otherwise would be required to induce anesthesia and so decrease the risk for adverse effects. Pre-anesthetic medication will increase the rate of induction of anesthesia and can reduce pre-operative pain and anxiety. Drugs include benzodiazepines for sedation and their muscle relaxant properties, opiates for pain relieve and anticholinergics or histamine Hi receptor antagonists against nausea and vomiting. Neuroleptics are also used as premedication for their antiemetic effects. 

Benzodiazepines and their congeners may help prevent central cortical-induced vomiting. A prominent side effect is drowsiness. They are frequently used in combination with other antiemetics for treating chemotherapy-related nausea and vomiting. Discussion of these agents is found in Chapter 30. 

Much more is known about overdose with the immediate-release formulation of bupropion than with the newer, SR and XL formulations. Reported reactions to overdose with the immediate-release form include seizures, hallucinations, loss of consciousness, and sinus tachycardia. Treatment of overdose should include induction of vomiting, administration of activated charcoal, and electrocardiographic and electroencephalographic monitoring. For seizures, an intravenous benzodiazepine preparation is recommended. 

Benzodiazepines such as lorazepam or diazepam are used before the initiation of chemotherapy to reduce anticipatory vomiting or vomiting caused by anxiety. The pharmacology of these agents is presented in Chapter 22. 

Lorazepam (Ativan, and others) is used as an adjunct to antiemetic regimens, particularly in patients with anticipatory vomiting. Alprazolam (Xanax) has also been used as an adjunct. Benzodiazepines can cause somnolence and amnesia lasting for several hours, which may be beneficial. 

If chemotherapy-associated nausea and vomiting are not well controlled, some patients develop nausea and vomiting in anticipation of their next chemotherapy treatment. This conditioned response, once it occurs, is often difficult to treat. Adequate early antiemetic treatment, particularly with regimens that include a benzodiazepine, may prevent this reaction. 

Flumazenll [floo MAZ eh nill] is a GABA receptor antagonist that can rapidly reverse the effects of benzodiazepines. The drug is available by IV administration only. Onset is rapid but duration is short, with a half-life of about one hour. Frequent administration may be necessary to maintain reversal of a long-acting benzodiazepine. Administration of flumazenil may precipitate withdrawal in dependent patients or may cause seizures if a benzodiazepine is used to control seizure activity. Dizziness, nausea, vomiting, and agitation are the most common side effects. 

Benzodiazepines The antiemetic potency of lorazepam and alprazolam (see p. 89) is low. Their beneficial effects may be due to their sedative, anxiolytic and amnesic properties. These same properties make benzodiazepines useful in treating anticipatory vomiting. 

Withdrawal signs from benzodiazepines like Xanax, Klonopin, Ativan, and Valium often begin with insomnia, irritability, and nervousness, progressing to more serious reactions such as abdominal cramps, muscle cramps, nausea or vomiting, trembling, sweats, hyperarousal and hypersensitivity to environmental stimuli, confusion, depersonalization, loss... 

Flumazenil is used as a benzodiazepine antagonist in the treatment of poisoning or the reversal of benzodiazepine effects in anesthesia 1,2) or in neonates (3). Guidelines for its use have been summarized (4). The problems in its use are those of dose adjustment, the risks of panic anxiety, seizures, or other signs of excessively rapid benzodiazepine withdrawal, and pharmacokinetic problems due to the short half-life of flumazenil (about 1 hour) compared with the longer half-lives of most benzodiazepines (5). Its use is also commonly associated with vomiting and headache, and rarely with psychosis or sudden cardiac death (SEDA-17,... 

Most side effects, such as transient yellowing of the skin and conjunctiva, a fluorescent cast to the mane, and the warm flush or early nausea occurring within 30 seconds of injection, can be explained to the patient before the procedure. Some practitioners advocate prophylaxis for nausea and vomiting, including administration of prochlorperazine, promethazine, or trimethoben-zamide, although there is no conclusive evidence for their benefit to patients. For patients likely to develop mticaria, premedication with systemic antihistamines is possible. Benzodiazepines, such as diazepam, may also be useful to control anxiety. 

Adverse effects of flumazenil can include brief anxiety, seizures in epileptics treated with a benzodiazepine and precipitation of withdrawal syndrome in dependent subjects. Rarely, vomiting is induced. 

Because of its relation to benzodiazepines, dependence on carisoprodol can be a problem. Among patients who had taken carisoprodol for 3 months or more, up to 40% had used it in amounts larger than prescribed, and up to 30% had used it for an effect other than that for which it was prescribed (2). A significant percentage of physicians were unaware of the potential of carisoprodol for abuse and of its metabolism to meprobamate. Patients with carisoprodol withdrawal can present with agitation, restlessness, hallucinations, seizures, anorexia, and vomiting. 

Various somatic complaints have been reported in patients in whom neuroleptic drugs are abruptly withdrawn (SEDA-20, 44). The incidence of these complaints varies widely in different reports, from 0 to 75%. Common complaints include headache, vomiting, nausea, diarrhea, insomnia, abdominal pain, rhinorrhea, and muscle aches. On rare occasions, the symptoms resemble those of benzodiazepine withdrawal (appetite change, dizziness, tremulousness, numbness, nightmares, a bad taste in the mouth, fever, sweating, vertigo, tachycardia, and anxiety), but it is possible that in some of the reported cases there was actually benzodiazepine withdrawal. Some of these symptoms may also have been linked to... 

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