Skeletal muscle relaxants sedative-hypnotics

Some agents (e.g., diazepam) also have wide use as skeletal muscle relaxants. Even though such may be the officially approved indications for various members of the BZD group, several clinically significant effects should be expected. The preponderance of one effect or the other may vary from one drug to another. Thus skeletal muscle relaxant, sedative-hypnotic, antianxiety, and anticonvulsant properties are all present. 

Diazepam (Valium, Diastat) [C-IVj [Anxiolytic, Skeletal Muscle Relaxant, Anticonvulsant, Sedative/Hypnotic/ Benzodiazepine] Uses Anxiety, EtOH withdrawal, muscle spasm, status epilepticus, panic disorders, amnesia, preprocedure sedation Action Benzodiazepine Dose Adults. Status epilepticus 5-10 mg IV/IM Anxiety 2-5 mg IM/IV Preprocedure 5-10 mg IV just prior to procedure Peds. Status epilepticus 0.5-2 mg IV/IM Sedation 0.2-0.5 mg/kg IV (onset w/in 5IV and 30 min IM duration about 1 h IV and IM) Caution [D, / -] Contra Coma, CNS depression, resp d es-sion, NAG, severe uncontrolled pain, PRG Disp Tabs 2, 5, 10 mg soln 1, 5 mg/mL inj 5 mg/mL rectal gel 2.5, 5, 10, 20 mg/mL SE Sedation, amnesia, bradycardia, i BP, rash, X resp rate Interactions T Effects W/ antihistamines, azole antifungals, BBs, CNS depressants, cimetidine, ciprofloxin, disulfiram, INH, OCP, omeprazole, phenytoin, valproic acid, verapamil, EtOH, kava kava, valman T effects OF digoxin, diuretics X effects w/ barbiturates, carbamazepine. 

Zolpidem [ban, inn] (zolpidem tartrate [usanJ Ambien Stilnoct and many other names) is one of the imidazopyridines, and a non-benzodiazepine BENZODIAZEPINE BINDING-SITE AGONIST. Most of its properties are similar to diazepam, but with less ANTICONVULSANT, SEDATIVE and SKELETAL MUSCLE RELAXANT properties. It has HYPNOTIC activity and has been used to treat insomnia, zolpidem tartrate zolpidem. 

II. Drugs utilized. Contrary to the popular belief that specific date rape drugs are involved In these crimes, a variety of drugs with amnestic or CNS depressant effects can be used to facilitate assault, including benzodiazepines, other sedative-hypnotic drugs, skeletal muscle relaxants, anticholinergics, hallucinogens, and of course, ethanol (Table 1-45). 

Sedative-hypnotic agents are widely used for the treatment of anxiety and insomnia. As a group they are one of the most frequently prescribed medications. Barbiturates (see p 124), benzodiazepines (p 130), antihistamines (p 96), skeletal muscle relax-ants (p 339), antidepressants (pp 88 and 90), and anticholinergic agents (p 84) are discussed eisewhere in this book. In this section (and Table 11-51) are listed some of the iess commoniy used hypnotic agents. 

E. Meprobamate has been reported to form tablet concretions In large overdoses, occasionally requiring surgical removal. Hypotension Is more common with this agent than with other sedative-hypnotics. Meprobamate Is the metabolite of skeletal muscle relaxant carisoprodol (see p 339). 

Various drugs have been used to treat muscle spasm. Most compounds in this group act as simple sedative-hypnotic agents and produce skeletal muscle relaxation indirectly. The drugs commonly used as skeletal muscle relaxants are listed in Table 11-53. Carisoprodol (Soma ) and baclofen have been abused as recreational drugs. I. Mechanism of toxicity... 

Kava pyrones are potent, centrally acting skeletal muscle relaxants. They act as hypnotics, antipyretics, sedatives, local anaesthetics, smooth muscle relaxants and antifungal agents. No interaction with benzodiazepine drugs or with moderate consumption of alcohol occurs, nor does kava impair mental alermess. However, continually chewing the root can destroy tooth enamel and eventually becomes habit forming (Bone 1994). 

Central Muscle Relaxants - There appeared during the year an excellent re-view oi the synthetic centrally acting skeletal muscle relaxants which covers the literature through most of 1966 ". As the authors, Donahoe and Kimura, point out, there continues to be a need for effective chemical compounds which relieve painful skeletal muscle spasms without producing muscular weakness or incapacitating sedative or hypnotic effects. Since most of the clinically useful compounds fall within a few structural classes there is a need for more basic studies involving molecular alteration for evaluation as central muscle relaxants. 

Table III Includes all use pairs with a frequency of occurrence greater than 5. The pair names and frequency of occurrence are presented in the table, as well as the distribution of these pairs over different size combinations. For example, the use pair analgesia-sedative occurs three times as a pair but also in three triple combinations with other uses hypnotic, narcotic, and skeletal muscle relaxant.

Some sedative-hypnotics, particularly members of the carbamate (eg, meprobamate) and benzodiazepine groups, exert inhibitory effects on polysynaptic reflexes and internuncial transmission and at high doses may also depress transmission at the skeletal neuromuscular junction. Somewhat selective actions of this type that lead to muscle relaxation can be readily demonstrated in animals and have led to claims of usefulness for relaxing contracted voluntary muscle in muscle spasm (see Clinical Pharmacology). Muscle relaxation is not a characteristic action of zolpidem, zaleplon, and eszopiclone. 

Benzodiazepines are used as hypnotics because they have the ability to increase total sleep time. They demonstrate minimal cardiovascular effects, but do have the ability to increase heart rate and decrease cardiac output. Most CNS depressants, including the benzodiazepines, exhibit the ability to relax skeletal muscles. Clozapine, a dibenzodiazepine, is used in the treatment of schizophrenia. It has both sedative and antipsychotic actions, and is the only FDA-approved medication indicated for treatment-resistant schizophrenia, and for reducing the risk of suicidal behavior in patients with schizophrenia. This drug can have potentially life-threatening side effects, but appears to have no abuse potential and will not be considered further. 

Muscle relaxation Relaxation of skeletal muscle occurs at high doses of most sedative-hypnotics. Diazepam is effective at sedative dose levels for specific spasticity states, including cerebral palsy. Meprobamate also has some selectivity as a muscle relaxant. 

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