Amnestic

Midazolam and diazepam decrease arterial pressure without a change ia heart rate. Like thiopeatoae, midazolam is a respiratory depressant. Advantages of midazolam are its amnestic effect, coupled with less postoperative depression (102). A reversal agent for the benzodiazepiaes has also become available. Flumazenil [78755-81-4] C25H24FN2O2, (5) displaces the beazodiazepiaes from their receptor but has Httie demoastrable activity of its owa (103,104). 

Glassification of Substance-Related Disorders. The DSM-IV classification system (1) divides substance-related disorders into two categories (/) substance use disorders, ie, abuse and dependence and (2) substance-induced disorders, intoxication, withdrawal, delirium, persisting dementia, persisting amnestic disorder, psychotic disorder, mood disorder, anxiety disorder, sexual dysfunction, and sleep disorder. The different classes of substances addressed herein are alcohol, amphetamines, caffeine, caimabis, cocaine, hallucinogens, inhalants, nicotine, opioids, phencyclidine, sedatives, hypnotics or anxiolytics, polysubstance, and others. On the basis of their significant socioeconomic impact, alcohol, nicotine, cocaine, and opioids have been selected for discussion herein. 

Anxiolytics are drugs used for the treatment of anxiety disorders. Apart from benzodiazpines, a frequently used anxiolytic is the 5HT1A (serotonin) receptor agonist buspiron, which has no sedative, amnestic or muscle-relaxant side effects, but whose action takes about a week to develop. Furthermore, it is less efficaceous than the benzodiazepines. Buspiron s mechanism of action is not fully understood. 

On the other hand, clinical and laboratory studies in humans have demonstrated the development of tolerance to the amnestic and analgesic effects of nitrous oxide and isoflurane (see Arnold et al. 1993 Avramov et al. 1990 Rupreht et al. 1985 Whitwam et al. 1976) and, in the case of ether or chloroform, to its reinforcing effects (Krenz et al. 2003). No studies have shown the development of tolerance to the reinforcing effects of nitrous oxide. 

NMBs does not possess sedative, amnestic, or analgesic properties... 

In most cases, the healthcare provider will not be in a position to witness a seizure. Many patients (particularly those with complex partial [CP] or GTC seizures) are amnestic to the actual seizure event. Obtaining an accurate history and description of the ictal event (including time course) from a third party is important. 

Short-term memory tasks increase high-affinity uptake of acetylcholine, whereas long-term reference memory tasks cause an acute increase followed by a long-lasting decrease and inhibition (Decker et al. 1988). In contrast, the drug scopolamine creates amnestic effects by blocking muscarinic receptors and decreasing acetylcholine levels. Thus, at... 

Cognitive effects A study of the effects of chiysin on memory was performed in the rat (Salgueiro et al. 1997). Chrysin does not have any amnestic effects on either acquisition or retention in three tests of memory (inhibitory avoidance, shuttle avoidance, and habituation to an open field), even at higher doses than required to produce anxiolytic effects. The cognitive effects of passionflower have not been examined in humans. 

Amnesia. Like dementia, the main feature of amnesia is memory loss. Amnesia, however, does not affect other intellectual abilities in the same manner as dementia. Distingnishing dementia from amnesia is most often a consideration when you evaluate memory problems in a chronic alcoholic. Alcoholics may become demented, but they may also develop an amnestic disorder known as Wernicke-Korsakoff syndrome. 

In addition to the benzodiazepine receptor agonists which, depending on the dose administered, have anxiolytic, anticonvulsant, sedative and amnestic properties, benzodiazepines have also been developed which block the action of agonists on this receptor. Such antagonists may be exemplified by... 

Mechanism of Action A benzodiazepine that enhances the action of gamma-ami-nobutyric acid, one of the major inhibitory neurotransmitters in the brain. Therapeutic Effect Produces anxiolytic, hypnotic, anticonvulsant, muscle relaxant, and amnestic effects. 

Organic amnestic syndrome, not induced by alcohol and other psychoactive substances... 

Benzodiazepines are highly effective anxiolytics and sedatives. They also have muscle relaxant, amnestic, and anticonvulsant properties. Benzodiazepines effectively treat both acute and chronic generalized anxiety and panic disorder. The high-potency benzodiazepines alprazolam and clonazepam have received more attention as antipanic agents, but double-blind studies also have confirmed the efficacy of diazepam and lorazepam in the treatment of panic disorder. Although only a few benzodiazepines are specifically approved by the... 

Zolpidem and zaleplon are hypnotics that act at the omega-1 receptor of the central GABA receptor complex. This selectivity is hypothesized to be associated with a lower risk of dependence. Unlike benzodiazepines, zolpidem and zaleplon do not appear to have significant anxiolytic, muscle relaxant, or anticonvulsant properties. However, amnestic effects may occur. 

Nevertheless, the GABAergic properties of benzodiazepines remain their most important clinical application. Over the past 30 years, the most widely used benzodiazepine drug has been diazepam (1.6). It is an anxiolytic, sedative, and muscle relaxant the anxious, depressed person becomes more outgoing and relaxed. There have been many diazepam analogs. Oxazepam (4.177) and lorazepam (4.178) have similar effects. Temazepam (4.179), flunitrazepam (4.180), and flurazepam (4.181) are useful sedative-hypnotics. Clonazepam (4.182) is a clinically useful anticonvulsant. Brotizolam (4.183), a novel benzodiazepine analog, seems to be an effective sedative-hypnotic. Midazolam (4.184) is an imidazolo-benzodiazepine that is water soluble and thus easily injectable. It is a hypnotic sedative with marked amnestic (i.e., memory loss) properties and is used in dentistry, endoscopic procedures, and induction to anesthetics in the elderly and in... 

The fact that single-dose administration of benzodiazepines could have marked amnestic effects was first recognized in anesthesiology where these drugs are used to relax and sedate patients prior to surgery. It was found that,... 

Box 7.4 Amnestic Effects of Benzodiazepines a Clinical Experiment in Anesthesiology... 

Some amnesia occurred after all three benzodiazepines, although there were pronounced differences between the three drugs with regard to the time of onset of action, peak effect and duration of action. For example the amnestic effect of diazepam occurred as soon as l min after injection but had abated completely 60 min later. 

C. Delirium, Dementia, Amnestic, and Other Cognitive Disorders... 

For example, low levels of thyroxine (T4) have been found in patients with significant confusion and memory problems after ECT. Furthermore, consistent with data from animal studies, 50 pg of triiodothyronine (T3) given before ECT diminished amnestic effects and accelerated the antidepressant effect of ECT (134). 

In one study, an inverse agonist was administered to human subjects producing anxiety, terror, cold sweats, tremor, agitation, fear of impending death, and intense inner strain (12). BZD antagonists apparently lack intrinsic activity, but may have both agonist and inverse agonist effects ( 13). For example, they are reported to reverse the increased anxiety that may occur after withdrawal of chronic BZD or alcohol use, and to reverse BZD-caused amnestic effects (14, 15,16 and 17). 

Several psychotic reactions to zolpidem have been reported-two cases of amnestic psychotic reaction and a psychotic reaction with hallucinations in an anorectic patient (151). Zolpidem 5 mg was prescribed for a 34-year-old woman with chronic insomnia. Twenty minutes after taking the recommended adult dose (10 mg), she experienced feelings of objects in her environment. She then slept uneventfully and recalled the unusual experience in the morning. Zolpidem may also cause transient cognitive and behavioral problems similar to those of BZDs (152). 

Dorow R, Berenberg D, Duka T, et al. Amnestic effects of lormetazepam and their reversal by the benzodiazepine antagonist Ro 15-1788. Psychopharmacology 1987 93 507-514. 

Kirk T, Roache JD, Griffiths RR. Dose-response evaluation of the amnestic effects of triazolam and pentobarbital in normal subjects. J Clin Psychopharmacol 1990 10 161-168. 

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