Psychotic effect

Most of the motor effects of amphetamine, especially stereotypy, are due to the release of DA as are its psychotic effects such as hallucinations. Its ability to mimic the action of DA in reward and reinforcement behaviour may contribute to its abuse potential (see Chapter 22) but its arousal (stimulant) properties also involve NA release. 

Szara, S. (1957) The comparison of the psychotic effect of tryptamine derivatives with the effects of mescaline and LSD-25 in self experiments. In Psychotropic Drugs, edited by S. Garattini and V. Ghetti, pp. 460-467. Elsevier, Amsterdam. 

Patients in whom haloperidol is contraindicated can be treated by intramuscular injection of benzodiazepines, but these can cause respiratory depression or respiratory arrest if given in too high a dose, are contra-indicated in patients with preexisting respiratory depression, and have no specific anti-psychotic effect. 

Those who abuse cocaine and other stimulants can also show psychotic effects which are not usually observed with marijuana. 

Kappa (k) Spinal and supraspinal analgesia Sedation constipation psychotic effects... 

Honey GD, Corlett PR, Absalom AR, Lee M, Pomarol-Clotet E, et al. 2008. Individual differences in psychotic effects of ketamine are predicted by brain function measured under placebo. J Neurosci 28 6295-6303. 

Synthetic drug of abuse with dangerous, addictive, psychotic effects... 

Agitation, which may occur in patients with dementia, can be treated with anti-psycho tics agents, mood stabilizing anticonvulsants, trazadone and anxiolytics (Doody et al., 2001). The atypical anti-psychotic medications are the treatment of choice for psychotic symptoms, such as hallucinations or delusions, particularly in those with Parkinsonism in whom dopamine receptor blockage is contraindicated due to the potential to worsen motor symptoms. In these patients, clozapine, which may reduce tremor in addition to its anti-psychotic effects, is particularly effective. However, rare cases of agranulocystosis necessitate weekly blood counts, and so limit its utility. Que-tiapine may be the next agent of choice because it appears to have fewer adverse motor effects than the other medications... 

D2 receptor. Neuroimaging studies have shown that an optimal D2 receptor occupancy of 60-70% is sufficient to produce an atypical anti-psychotic effect, and if D2 receptor occupancy is too high, the atypical profile can be lost even in the presence of high 5-HT2 occupancy. Several atypical anti-psychotics with low D2/5-HT2 binding ratios have now been introduced onto the market such as ziprasidone 11. 

In order to explain the unique antipsychotic phenomenon one may reasonably postulate that the lithium ion must interact with specific receptors . Such an assumption requires that (i) specific receptors exist, (ii) the receptors selectively bind lithium in the presence of other cations known to exist in biological tissue in appreciable higher concentrations, and (iii) binding of lithium to the receptor triggers some mechanism responsible for the suppression of the psychotic effect. 

It is usual to classify as psychotomimetic, substances which produce predominantly psychotic effects in low concentrations. Many other drugs (cocaine, amphetamine and atropine, for instance) have psychotomimetic side effects or are effective psychotomimetics in relatively high doses. They are, therefore, not usually grouped with the psychotomimetic drugs, but since the criteria of psychotomimetic action are rather imprecise, differences of opinion do arise concerning the classification of some of the less active substances. The names and formulae of some of the compounds generally recognized as psychotomimetic are set out in Table 5.6. 

HEALTH SYMPTOMS inhalation (somnolence, convulsions, anti-psychotic effects, respiratory failure, dizziness, headache, shortness of breath, nausea, increased blood pressure, collapse) skin/eye contact (redness) skin absorption (excitement, stupor, weakness) ingestion (symptoms parallel those of inhalation). 

In the history of ethnopharmacology, a most significant event was the isolation and clinical application of the alkaloid reserpine from Rauwolfia spp, a plant that had been used for millennia in the Ayurvedic tradition to treat "madness". Although reserpine had clearly demonstrated antipsychotic efficacy, it was soon replaced by the first synthetic antipsychotic, chlorpromazine, which proved more effective, had fewer side-effects and was relatively inexpensive to manufacture [44]. Exhibit 4 provides overviews for representative studies on natural products with putative anti-psychotic effects. 

Nalbuphine (trade name in Germany and elsewhere Nubain ) is a mixed agonist-antagonist. The danger of hallucinations and psychotic effects is lower than for other dualistic opioids. The addiction potential is likewise low, so that nalbuphine is not subject to regulatory control as a narcotic. 

N,N-dimethyltryptamine has psychotic effects in man similar to those of lysergic acid diethylamide. According to investigations of Rosenberg et, iV-dimethyltryptamine leads to psychotic effects such as... 

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