Benzodiazepine anterograde amnesia with

The definition of desired therapeutic and side effects in the case of the benzodiazepines very much depends on the clinical problem in question. The sedative and hypnotic actions are desired effects in the treatment of insomnia, but undesired effects in the treatment of anxiety disorders. Effects that are usually undesired include daytime drowsiness, potentiation of the sedative effects of ethanol, and anterograde amnesia. They are mediated via the benzodiazepine site of GABAa receptors, since they can be antagonized with flumazenil. 

Anterograde amnesia has been reported with most benzodiazepines. Using the lowest dose possible minimizes amnesia. 

Benzodiazepines are associated with anterograde amnesia, especially when they are administered intravenously and in high doses. 

The most widely studied aspect of cognition with respect to benzodiazepines is memory.12 163 One of the most reliable effects of benzodiazepines is to impair recall of information presented after drug administration (anterograde amnesia). In contrast, information presented before administration of benzodiazepines is not affected. The memory decrement produced by benzodiazepines is a function of task difficulty, such that little or no impairment is observed for immediate recall of a few items, whereas more complex or delayed memory tests reveal profound impairment.12 The benzodiazepine antagonist flumazenil has been used to block the sedative effects of benzodiazepines, but the amnestic effect was not affected, suggesting that benzodiazepine-induced amnesia is independent of sedation.122,164 It has also been demonstrated that some benzodiazepines selec-... 

The sleep-promoting effects of benzodiazepines may relate to their ability to reduce hyperarous-ability and emotional tension. The anterograde amnesia produced by high doses may be due to their interference with hippocampal functions. 

Although the BZDs have minimal depressant effects on respiration, when combined with other CNS depressants (alcohol, opioids), BZDs can cause fatal respiratory suppression. However, most non-BZD sedatives may also cause death by suppression of breathing and heart failure if taken in sufficient quantity. Benzodiazepines can also cause some degree of memory loss called anterograde amnesia—a form of amnesia that involves the formation of memories after a specific event a person with anterograde amnesia cannot remember information presented to them after ingesting the BZD, a process similar to an alcohol black-out. 

As with some, but not all benzodiazepines, anterograde amnesia of varying severity and paradoxical reactions have been reported following therapeutic doses of HALCION. Data from several sources suggest that anterograde amnesia may occur at a higher rate with HALCION than with other benzodiazepine hypnotics. 

Anterograde amnesia may be more likely with triazolam than with other sedative benzodiazepines... 

A more recently recognized problem is that benzodiazepines may interfere with the storage of memories, a phenomenon called anterograde amnesia. Thus, when an individual is awakened by a phone call from sleep induced by benzodiazepines, he or she may fail to remember the phone conversation. The drug may be present in... 

The benzodiazepines are primarily administered for their sedative-hypnotic effects. Benzodiazepines are commonly used as anxiolytics, muscle relaxants, anticonvulsants, and to treat alcohol withdrawal, insomnia, and agitation. They are administered pre-operatively for their anterograde amnesia effects and are combined frequently with other medications for conscious sedation before procedures. They are also utilized as drugs of abuse. 

Verwey B, Muntendam A, Ensing K, et al. (2005) Clinically relevant anterograde amnesia and its relationship with blood levels of benzodiazepines in suicide attempters who took an overdose. Progress in Neuro-Psycho-pharmacology and Biological Psychiatry. 29(1) 47-53. 

Virtually all effects of the benzodiazepines result from their actions on the central nervous system (CNS). The most prominent of these effects are sedation, hypnosis, decreased anxiety, muscle relaxation, anterograde amnesia, and anticonvulsant activity. Only two effects of these drugs result from peripheral actions coronary vasodilation, seen after intravenous administration of therapeutic doses of certain benzodiazepines, and neuromuscular blockade, seen only with very high doses. 

Anesthesia At high doses loss of consciousness may occur, with amnesia and suppression of reflexes. Anterograde amnesia is more likely with benzodiazepines than with other sedative-hypnotics. Anesthesia can be produced by most barbiturates (eg, thiopental) and certain benzodiazepines (eg, midazolam). 

Pharmacological premedication is usually prescribed for patients with planned overnight hospital stay. Low-dose benzodiazepines provide anxiolysis, light sedation and anterograde amnesia. Especially at advanced age, benzodiazepines may elicit paradoxical reactions or predispose to postoperative delirium. Alternatives for oral premedication are clonidin or haloperidol. Ambulatory patients usually do not receive preoperative sedatives. 

Sedation and amnesia without analgesia are provided by midazolam i.v. or, less commonly nowadays, diazepam. These drugs can be used alone for procedures causing mild discomfort, e.g. endoscopy, and with a local anaesthetic where more pain is expected, e.g., removal of impacted wisdom teeth. Benzodiazepines produce anterograde, but not retrograde, amnesia. By definition, the sedated patient remains responsive and cooperative. (For a general account of benzodiazepines and the competitive antagonist flumazenil, see Ch. 19.)... 

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