Hypnotics anticholinergic

The antiemetics and antivertigo drug may have additive effects when used with alcohol and other CNS depressants such as sedatives, hypnotics, antianxiety drugp, opiates, and antidepressants. There may be additive anticholinergic effects (see Chap. 25) when administered with drag s that have anticholinergic activity such as the antihistamines, antidepressants, pheno-thiazines, and disopyramide The antacids decrease absorption of the antiemetics. 

The antidiarrheal drugs cause an additive CNS depression when administered with alcohol, antihistamines, narcotics, and sedatives or hypnotics. There are additive cholinergic effects when administered with other drugp having anticholinergic activity, such as antidepressants or antihistamines. Concurrent use of the antidiarrheals witii a monoamine oxidase inhibitor increases the risk of a hypertensive crisis. 

A number of medications have been associated with an increased risk of falling, including drugs affecting mental status such as antipsychotics, benzodiazepines, tricyclic antidepressants, sedative-hypnotics, anticholinergics, and corticosteroids. Some cardiovascular and antihypertensive drugs also can contribute to falls, especially those causing orthostatic hypotension.9... 

Information about prescription drag use alcohol or other substance use family medical history and history of trauma, depression, or head injury should be obtained. It is important to rule out medication use as a contributor or cause of symptoms (e.g., anticholinergics, sedatives, hypnotics, opioids, antipsychotics, and anticonvulsants) as contributors to dementia symptoms. Other medications may contribute to delirium, e.g.,... 

Antagonists. Most of the so-called Hi-antihistamines also block other receptors, including M-cholinoceptors and D-receptors. Hi-antihistamines are used for the symptomatic relief of allergies (e.g., bamipine, chlorpheniramine, clemastine, dimethindene, mebhydroline pheniramine) as antiemetics (meclizine, dimenhydrinate, p. 330), as over-the-counter hypnotics (e.g., diphenhydramine, p. 222). Promethazine represents the transition to the neuroleptic phenothiazines (p. 236). Unwanted effects of most Hi-antihistamines are lassitude (impaired driving skills) and atropine-like reactions (e.g., dry mouth, constipation). At the usual therapeutic doses, astemizole, cetrizine, fexofenadine, and loratidine are practically devoid of sedative and anticholinergic effects. Hj-antihistamines (cimetidine, ranitidine, famotidine, nizatidine) inhibit gastric acid secretion, and thus are useful in the treatment of peptic ulcers. 

Drugs that may be affected by dronabinol include amphetamines, cocaine, sympathomimetics, anticholinergics, antihistamines, tricyclic antidepressants, alcohol, sedatives, hypnotics, psychomimetics, disulfiram, fluoxetine, and theophylline. 

Chlorpromazine has direct effects on the CTZ and may also depress temperature control and prevent shivering. The effects are due to inhibition of dopamine centrally. It may potentiate the effects of hypnotics, sedatives and anaesthetic agents. It is rarely used in anaesthetic practice today. Promethazine was first developed for its antihistamine effects but is more commonly used for its sedative/anticholinergic, anti-emetic actions, and prevention of motion-related sickness. The sedative actions are quite marked and last longer than the anti-emetic effects. 

There are also numerous antidepressants that have sedative-hypnotic properties (Table 8—4). Some of these antidepressants are sedating owing to anticholinergic-antihistaminic actions. Not surprisingly, the tricyclic antidepressants (TCAs) can therefore be useful hypnotics to induce sleep in some patients. Thus, skillful use of a TCA in a depressed patient with insomnia can turn the liability of unwanted sedation into the asset of relief of insomnia if the TCA is given at bedtime. This property, as discussed in Chapter 6, has nothing to do, however, with the reason that TCAs are antidepressants (shown in Figs. 6—15 and 6—16). 

Paroxetine has mild anticholinergic actions that can enhance the rapid onset of anxiolytic and hypnotic efficacy but also cause mild anticholinergic side effects... 

A sedative-hypnotic is administered the night before surgery to assist with sleep. An hour before the surgery, premedications are administered to sedate and decrease anxiety. Premedications are an anticholinergic (atropine) to decrease secretions and either a narcotic analgesic or benzodiazepine. 

Clinically important, potentially hazardous interactions with alcohol, anticholinergics, barbiturates, benzodiazepines, butabarbital, chloral hydrate, chlordiazepoxide, chlorpromazine, clonazepam, clorazepate, diazepam, ethchlorvynol, fluphenazine, flurazepam, hypnotics, lorazepam, MAO inhibitors, mephobarbital, mesoridazine, midazolam, narcotics, oxazepam, pentobarbital, phenobarbital, phenothiazines, phenylbutazone, primidone, prochlorperazine, promethazine, quazepam, secobarbital, sedatives, temazepam, thioridazine, tranquilizers, trifluoperazine, zolpidem... 

Toxic syndromes ( toxidromes ) are clinical syndromes that are essential for the successful recognition of poisoning patterns. A toxidrome is the constellation of clinical signs and symptoms that suggests a specific class of poisoning. The most important toxidromes are (1) anticholinergic, (2) cholinergic, (3) opioid and opioid withdrawal, (4) sedative-hypnotic and sedative-hypnotic withdrawal, and (5) sympathomimetic. Symptoms for these toxidromes are listed in Table 34-2. 

Overall the anthiistamines are relatively safe. However, their CNS depressant actions are enhanced by co-ingestion of ethanol, sedative-hypnotic drugs, and opioids their anticholinergic actions are potentiated by co-ingestion of tricyclic antidepressants and phenothiazines. Therefore the... 

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