Hypnotics indications

Other apphcations of sodium bromide iaclude use ia the photographic iadustry both to make light-sensitive silver bromide [7785-23-1] emulsions and to lower the solubiUty of silver bromides during the developing process use as a wood (qv) preservative in conjunction with hydrogen peroxide (14) as a cocatalyst along with cobalt acetate [917-69-1] for the partial oxidation of alkyl side chains on polystyrene polymers (15) and as a sedative, hypnotic, and anticonvulsant. The FDA has, however, indicated that sodium bromide is ineffective as an over-the-counter sleeping aid for which it has been utilized (16). 

Phenytoin. Phenytoin sodium is sodium diphenylhydantoin [630-93-3] which is stmcturally related to the barbiturates. It was originally introduced as an anticonvulsant (18) (see Hypnotics, sedatives, and anticonvulsants) and later found to have antiarrhythmic properties (19), although not approved by the PDA for any arrhythmic indications. Phenytoin is effective in the treatment of ventricular arrhythmias associated with acute MI and with digitalis toxicity (20). It is not very effective in treatment of supraventricular arrhythmias (20). 

Benzodiazepines and similar agents occupy a position of intermediate abuse potential, compared with most other sedative-hypnotics (Griffiths and Weerts 1997). Animal models of abuse habihty indicate that the reinforcing effects of benzodiazepines are less pronounced than are those of the barbiturates, opioids, and stimulants. Differences in abuse potential within the class have not been consistently demonstrated however, most chnicians agree that benzodiazepines with a rapid onset and short duration of action pose the greatest risk in susceptible individuals. 

Other sedative-hypnotic medications, such as barbiturates, may play a useful role in severe withdrawal from this group of drugs. For example, in a case series of GBL withdrawal, use of intravenous pentobarbital in the range of 1-2 mg/kg/hour lowered the total requirement for intravenous lorazepam (Sivilotti et al. 2001). Antipsychotic medications are often used to reduce psychotic agitation. However, because antipsychotic medications lower the seizure threshold and may contribute to loss of central control of temperature leading to hyperthermia or neuroleptic malignant syndrome (NMS), they are not indicated as first-line medications for GHB withdrawal delirium (Dyer and Roth 2001 McDaniel and Miotto 2001 Sharma et al. 2001). If anti-... 

There are now indications for the interaction of progesterone metabolites with the Cl channel of the GABAa receptor (Fig. 52-7). The A-ring-reduced steroids, especially those with the 5a,3a configuration, are particularly active on the GABAa receptor [ 12]. By facilitating chloride-channel opening, these steroids produce anesthetic, anxiolytic and sedative-hypnotic effects (see Ch. 16). 

The development of the benzodiazepine class of drugs for the treatment of a variety of neurological indications has proven to be an outstanting success story in the field of chemotherapy. However, these compounds often produce undesirable side effects when used as anti-anxiety or hypnotic agents. These side effects include sedation, physical dependence, amnesia, muscle relaxation, and ethanol potentiation. The development of a benzodiazepine receptor-based anxiolytic agent devoid of these side effects would constitute a major advance in the field and has been the focus of significant research efforts [284]. 

Adults. 3 g PO q6h x 4 PRN Supl 1-2 g IM or IV repeat PRN Preeclampsia/pre-mature labor 4 g load then g/h IV inf Cardiac arrest 1-2 g IV push (2-4 mL 50% soln) in 10 mL DjW AMI Load 1-2 g in 50-100 mL D5W, over 5-60 min IV then 0.5-1.0 g/h IV up to 24 h (ECC 2005) Feds. 25-50 mg/kg/dose IM or IV q4-6h for 3-4 doses repeat PRN dose w/ low urine output or renal insuff Caution [B, +] Contra Heart block, renal failure Disp Inj 10, 20, 40, 80, 125, 500 mg/mL bulk powder SE CNS depression, D, flushing, heart block Interactions T CNS depression W/ antidepressants, antipsychotics, anxiolytics, barbiturates, hypnotics, narcotics EtOH T neuromuscular blockade Wf aminoglycosides, atracurium, gallamine, pancuronium, tubocurarine, vecuronium EMS Check for absent patellar reflexes this may indicate tox may cause hypokalemia (flattened T waves) and hypocalcemia OD May cause hypotension, resp arrest, T PR, QRS, and QT interval, AV block, and cardiac arrest calcium salts can be given to reverse resp depression... 

Zolpidem (1) is an effective hypnotic agent indicated for the short-term treatment of insomnia. Zolpidem interacts with the GABAa receptor, and its pharmacological effect is blocked by the benzodiazepine-receptor antagonist fiumazenil (Sanger and Depoortere, 1998). Zolpidem displaces benzodiazepines more selectively from the cerebellum than the hippocampus or spinal cord, consistent with preferential interaction with the ajGABAA receptor subtype (sometimes referred to as the benzodiazepine coi receptor). Studies... 

It does not cause cognitive impairment and has a low potential for abuse. It does not show withdrawal reactions and has no anticonvulsive, hypnotic, muscle relaxant and sedative effects. The anxiolytic effect gradually evolves over 1-3 weeks, it does not potentiate the sedative effects of alcohol and is indicated for the short-term management of generalized anxiety disorder. 

Guidance on the clinical indications for benzodiazepine therapy is available from various sources (Task Force Report of the American Psychiatric Association 1990 Ballenger et al. 1998a Bandelow et al. 2002). Long-term therapy is most likely to present problems with discontinuation and is usually reserved for cases that have proved resistant to treatment with antidepressants alone. Patients may benefit from a 2-4 week course of a benzodiazepine whilst antidepressant therapy is initiated, as this counteracts the increased anxiety caused by some drugs (Goddard et al. 2001). A benzodiazepine maybe useful as a hypnotic in some cases of anxiety disorder, and can be used by phobic patients on an occasional basis before exposure to a feared situation. 

The benzodiazepines constitute the most commonly used group of anxiolytics and sedative-hypnotics. Since the first member of this group, chlordiazepoxide, was introduced, many congeners have been marketed. Most of these drugs possess anxiolytic, sedative-hypnotic, and anticonvulsant properties. Thus, the clinical indications for specific benzodiazepines are not absolute, and their uses overlaps considerably. 

It is indicated as hypnotic, in anxiety, tension, muscle spasm, psychosomatic and behaviour disorders, dysmenorrhoea, cerebral palsy, upper motor neuron spasticity, sedative for surgical procedures, labour, tetanus, eclampsia and epilepsy. 

Anxiolytics and Sedative-Hypnotics. Because of their large therapeutic index, measurement of anxiolytic or sedative-hypnotic serum concentrations is not usually necessary in clinical practice, unless abuse, overdose, or inadvertent toxicity are suspected. Some data indicate that plasma alprazolam levels of 40 ng/mL may be required to manage panic disorder ( 51) (see the sections Adverse Effects of Anxiolytics and Adverse Effects of Sedative-Hypnotics in Chapter 12). 

Available evidence indicates that systematic desensitization and in vivo exposure are the most effective treatment methods available. Pharmacological treatment has not been well investigated, but studies involving antidepressants suggest that TCAs and MAOIs are ineffective ( 85, 86 and 87). In addition, three studies suggest that sedative-hypnotic anxiolytics may undermine the behavioral treatment of specific phobias (88, 89 and 90). In another study, volunteers with animal phobias were exposed to their phobic object 1.5 hours after administration of either tolamolol, diazepam, or placebo in a double-blind crossover design. Tolamolol abolished the stress-induced tachycardia but had no beneficial behavioral or subjective effects ( 91). 

This non-BZD hypnotic, cyciopyrroione, is indicated for short-term management of insomnia. Zopiclone has a BZD-like profile, a short half-life of 3.5 to 6.5 hours, no active metabolites, minimal rebound effects, and less abuse potential than BZDs. The usual therapeutic dose is oral 7.5 mg administered 30 to 60 minutes before bedtime. Zopiclone has a well-documented capacity to reduce sleep latency, improve quality and duration of sleep, and reduce the frequency of nighttime awakenings. In clinical trials, 7.5 mg doses of zopiclone have been found to be as effective as triazolam 0.5 mg, temazepam 20 mg, flurazepam 15-30 mg, and nitrazepam 5 to 10 mg for the short-term treatment of insomnia (136). 

The data on zaleplon to date indicate that it has some advantages over other hypnotics, including a favorable safety profile, as indicated by the absence of rebound insomnia and withdrawal symptoms when zaleplon is discontinued (162). In addition, when taken by a nursing mother, zaleplon is transferred through breast milk to her infant in such very small quantities that this is unlikely to be important ( 163). 

The decision to use these agents should be made with considerable caution, and only after possible underlying causes of the patient s symptoms have been explored and treated appropriately. Although surveys indicate that BZDs are frequently prescribed for elderly patients, the NIH Consensus Development Conference stated that the efficacy and safety of sedatives and hypnotics have not been established for older people, nor has the extent to which they contribute to or alleviate sleep problems (302, 305, 306). Saizman (307) has pointed out that relatively few research studies, most of which are seriously flawed, have examined the therapeutic effect of these agents in elderly patients. Thus, recommendations for the use of BZDs in elderly patients are derived almost exclusively from studies of young adult patients, studies of pharmacokinetics and toxicity in elderly patients, and clinical and anecdotal experience. 

Between 1980 and 1991, only a few published studies examined the safety and the hypnotic efficacy of the 0.125-mg dose of triazolam in elderly patients ( 318, 319, 320, 321, 322, 323 and 324). These studies and case reports indicate that with continued use, the initial efficacy of the 0.125-mg dose of triazolam in elderly patients begins to wane after 1 week and progressively diminishes to ineffectiveness, usually by the sixth week of continuous administration. During the same period, the risk of potentially serious adverse reactions increases. 

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