Antipsychotics sedation

Pseudoparkinsonism Akathisia Sedation Antipsychotics Sedative/hypnotics Tricyclic antidepressants Muscle relaxants... 

Antipsychotic drugs have inconsistent effects on sleep patterns but tend to normalize sleep disturbances characteristic of many psychoses and mania. The capacity to prolong and enhance the effect of opioid and hypnotic drugs appears to parallel the sedative, rather than the neuroleptic, potency of a particular agent thus, potent, less-sedating antipsychotics do not enhance sleep. 

Aripiprazole 5.25-15 mg IM (usually 9.75mg) 30 mg Less sedating antipsychotic Better than olanzapine if hypotensive IM - wait 2 h before repeat max 3 doses in 24 h... 

The antipsychotic drugs may cause extreme drowsinessand sedation, especially during the first or second weeks of therapy. This reaction may impair mental of physical abilities Dro wsness usually diminishesafter 2-3 weeks of therapy. However, if the patient continuesto be troubled by drowsiness and sedation, the physician may prescribe a lower dosage. 

There is an increased risk of sedation and delirium with increased age. There is also an increased risk of antidopaminergic effects such as parkinsonism due to antipsychotic drugs. Many other drugs that pass the blood-brain barrier may cause adverse effects in the elderly. The response of opioids may be increased in the elderly, resulting in oversedation (Turnheim 1998). 

These medications cannot be dosed solely based on their dopamine receptor blocking potency, because they also have effects on other receptors that must be factored into their dosing (see Table 4.6). For example, it is not unusual to begin treatment of a psychotic patient with a 5 mg dose of haloperidol. In terms of dopamine receptor blocking potency, 5 mg of haloperidol is more or less equivalent to 500 mg of chlorpromazine. If a patient were immediately treated with 500 mg of chlorpromazine, however, he/she would likely have side effect problems such as dizziness and excessive sedation. This is because the medications with the lowest dopamine receptor blocking potency are the most potent at other receptor systems responsible for these side effects. (See Table 4.7) The evolution of antipsychotics from low to medium to high potency has been driven not only by the desire to find... 

Antipsychotics also have a troublesome side effect burden that includes an often-irreversible movement disorder known as tardive dyskinesia (TD). Other side effects include so-called parkinsonism, dystonic reactions (i.e., abrupt onset of muscle spasms), akathisia (an uncomfortable sense of motoric restlessness), sedation, weight gain, dizziness, dry mouth, and constipation among others. These side effects, in particular the risk for TD, limit the usefulness of antipsychotics in the treatment of ADHD, and at this time the typical antipsychotics cannot be considered a reasonable monotherapy in uncomplicated ADHD. 

Other sleep-inducing benzodiazepines should be avoided. They are more difficult to metabolize and can accumulate in elderly, demented patients. Sedating, low potency antipsychotics should also be avoided. Their strong anticholinergic (acetylcholine-blocking) effects can worsen dementia or cause delirium. 

What Is a Side Effect This chapter picks up where Chapters 1 and 2 left off. As we discussed in the earlier chapters, all medications, psychiatric and otherwise, have multiple effects. One takes a medication to achieve a therapeutic effect. Occasionally, a single medication may have more than one therapeutic effect. All other effects are side effects. Different medications may have differing therapeutic and side effects depending on the intended use. For example, trazodone and quetiapine are often prescribed to aid in sleep, and in this instance sedation is the desired effect, yet when used as an antidepressant and antipsychotic, respectively, the sedation is often an unwanted effect. Psychotropic medications typically have multiple effects. First, they usually interact with more than one nerve cell protein, be it a transporter or a receptor. Quite often, one of the medication s receptor or transporter interactions produces the therapeutic effect. The other interactions tend to not be involved in the therapeutic effect and only serve to produce side effects. Sometimes a neurotransmitter will have multiple different receptor types, but the medication interacts with... 

Largactil is a proprietary preparation of chlorpromazine, an aliphatic antipsychotic with marked sedation and moderate antimuscarinic and extrapyramidal side-effects. Serenace is a proprietary preparation of haloperidol, a butyrophenone antipsychotic with marked extrapyramidal side-effects, moderate sedation but not very likely to cause hypotension. Tegretol is a proprietary preparation of carbamazepine, an anti-epileptic drug indicated in partial and secondary generalised tonic-clonic seizures, primary generalised tonic-clonic seizures, trigeminal neuralgia and in the prophylaxis of bipolar disorder unresponsive to lithium. 

Prochlorperazine is a potent phenothiazine antipsychotic drug that is associated with a high risk of extrapyramidal side-effects, a low degree of sedation and of antimuscarinic side-effects. Chlorpromazine is less likely to induce extrapyramidal side-effects but has increased risks of inducing sedation and antimuscarinic side-effects. Olanzapine is classified as an atypical antipsychotic having characteristically much fewer incidences of extrapyramidal... 

Neuroleptic activity profiles. The marked differences in action spectra of the phenothiazines, their derivatives and analogues, which may partially resemble those of butyrophenones, are important in determining therapeutic uses of neuroleptics. Relevant parameters include antipsychotic efficacy (symbolized by the arrow) the extent of sedation and the ability to induce ex-trapyramidal adverse effects. The latter depends on relative differences in antagonism towards dopamine and acetylcholine, respectively (p. 188). Thus, the butyrophenones carry an increased risk of adverse motor reactions because Lullmann, Color Atlas of Pharmacology 2000 Thieme All rights reserved. Usage subject to terms and oonditlons of lloense. 

From the pharmacological point of view antipsychotics are subdivided into two groups, the newer atypical and older typical. They work in different ways. The newer atypicals tend to have fewer side effects and are generally less sedating. 

Pharmacology The tricyclic antidepressants (TCAs), structurally related to the phenothiazine antipsychotic agents, possess 3 major pharmacologic actions in varying degrees Blocking of the amine pump, sedation, and peripheral and central... 

Antipsychotic agent Approx. equiv. dose (mg) Usual oral adult daily dose range (mg) Sedation EPS Anticholinergic effects ... 

The impact of antipsychotic agents on consciousness is immediately apparent from the frequency with which sedation and drowsiness are reported as side effects (Tune et ah, 1991), a property which historically has been used as a treat-... 

Atypical antipsychotics have advantages in tolerabihty and safety over the older drugs. They have a lower incidence of extrapyramidal movement disorders, but may cause sedation and weight gain. Their metabolism by CYP450 enzymes leads to a potential for interaction with many co-prescribed drugs. 

Sedation is common after use of all antipsychotic drugs and is especially notable with the low-potency phenoth-iazines this is a result of their activity at aj-adrenergic and Hi-histaminergic receptors. However, sedation decreases during long-term treatment, and many patients become tolerant to this effect. Single daily doses given at bedtime minimize this problem. 

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