Psychosis haloperidol

Psychiatric Disorders. The main indications for DA antagonists are the treatment of adult schizophrenia, and childhood psychosis. Haloperidol and chlorpromazine are the most frequently employed. 

The close resemblance between schizophrenia and PCP-induced psychosis suggests that the behavioral effects produced by PCP might be useful as a model of psychosis. On this basis, most animal studies have examined the ability of various agents to modify PCP-induced hyperactivity and stereotypy. While some studies suggest that neuroleptics such as haloperidol (Castellani and Adams 1981 Garey et al. 1980), chlorpromazine, or clozapine (Freed et al. 

Giannini, A.J. Eighan, M.S. Loiselle, R.H. and Giannini, M.C. Comparison of haloperidol and chiorpromazine in the treatment of phencyclidine psychosis. J. Clin Pharmacol 244 202-204, 1984. Grove, V.E. Painless self-injury after ingestion of "angel dust." TAMA 242 655, 1979. 

Cocaine or stimulant intoxication may require administration of a small dose of a short-acting benzodiazepine (e.g., lorazepam 1 to 2 mg) for agitation or severe anxiety. Antipsychotics (e.g., haloperidol 2 to 5 mg) should be used only if psychosis is present. If hyperthermia is present, initiate cooling measures. 

With the introduction of chlorpromazine in 1952, there was a small revolution in psychiatry patients suffering from psychosis were able to be de-institutionalized. Chlorpromazine and other typical antipsychotics (e.g., haloperidol) demonstrate high in vitro binding affinities for the dopamine D2 receptor (D2). Specifically, their... 

Gjedde, A. and Wong, D. F. Quantification of neuroreceptors in living human brain, v. Endogenous neurotransmitter inhibition of haloperidol binding in psychosis. /. Cereb. Blood Flow Metab. 21 982-994,2001. 

Antipsychotics Haloperidol 025 1-3 Psychosis hallucinations, delusions, suspiciousness... 

Delusions/Psychosis. Demented patients who are acutely psychotic and agitated should be treated in much the same manner as demented patients with delirium. Low doses of a high potency conventional antipsychotic like haloperidol were once preferred. This was mainly because it can be given both orally and by injection. In recent years, the atypical antipsychotic ziprasidone, which is now also available in oral and injectable forms, has superseded haloperidol as the preferred agent when treating the acutely psychotic and agitated patient with dementia. As previously noted, ziprasidone affords the same tranquilizing benefit as haloperidol, it can now be administered via injection when necessary, and it avoids the problematic extrapyramidal symptoms of haloperidol to which patients with dementia are often keenly sensitive. 

Chronic stimulant abuse alters the personality of the abuser. These and related changes are the result of neurotoxicity and are not characterized as either acute drug effects or withdrawal signs. Individuals have delusions of being pursued or persecuted and therefore become suspicious and paranoid. They become self-occupied and hostile toward others. Long-term abuse can produce toxic psychosis that closely resembles schizophrenia and must be treated with neuroleptic drugs (haloperidol, chlorpromazine). This psychosis can develop even within 1 to 2 weeks if the person is on a run of very high doses of stimulants. 

C. Abuse of stimulants can produce toxic psychosis that closely resembles schizophrenia. An agent such as haloperidol or a phenothiazine will provide im-... 

Efficacy in short-term treatment. From studies in adult schizophrenia, it is evident that clozapine treatment has at least the same or superior antipsychotic effect, compared to typical antipsychotics. In some studies, clozapine was superior with regard to symptom reduction in severe and acute schizophrenic patients. As the guidelines do not allow the use of clozapine as a first-choice drug, most patients have been treated before with at least two atypical or typical antipsychotics. Only one controlled trial has assessed the efficacy of clozapine in child and adolescent psychiatry. In this study (Kumra et ah, 1996), clozapine was found to be superior to haloperidol in all measures of psychosis, and showed a striking superiority for both positive and negative symptoms. 

Psychosis Intravenous haloperidol Risperidone/atypicals Low potency neuroleptics... 

Zhang-Wong J, Zipursky RB, Beiser M, et al Optimal haloperidol dosage in first-episode psychosis. Can J Psychiatry 44 164—167, 1999... 

For example, withdrawal of haloperidol in one patient revealed little change in either mental status or involuntary movements 3 weeks after discontinuation ( 478). In contrast, there was a marked deterioration in mental status and involuntary movements in this same patient 1 week after clozapine withdrawal. This rebound psychosis was attributed to increased dopamine release, a mechanism suggested by earlier observations made after withdrawal studies in humans and animals. For example, a study of the effects of abrupt withdrawal in rats showed increased and decreased striatal basal dopamine release with discontinuation of clozapine and haloperidol, respectively ( 479). The exacerbation of dyskinesia after clozapine withdrawal suggests that human nigrostriatal dopamine receptors (putatively involved in the emergence of dyskinetic movements) may be altered pharmacologically by this drug. 

Bleeker JAC, Dingemans PM, Frohne-de Winter ML, et al. Plasma level and effect of low dose haloperidol in acute psychosis. Psychopharmacol Bull 1984 20 317-319. 

Janicak PG, Javaid Jl, Sharma RP, et al. A two-phase, double-blind randomized study of three haloperidol blood levels for acute psychosis with reassignment of initial non-responders. Acta Psychiatr Scanc11997 95 343-350. 

Lerner Y, Lwow E, Levitin A, et al. Acute high-dose parenteral haloperidol treatment of psychosis. Am J Psychiatry 1979 136 1061-1064. 

Among the atypical antipsychotics, clozapine has the most convincing evidence of efficacy in children and adolescents with schizophrenia ( 166,167, 170). Kumar and colleagues (171) conducted a double-blind, randomized trial of clozapine versus haloperidol in 21 children and adolescents (mean age = 14 years) whose psychosis had been previously unresponsive to typical antipsychotics. Clozapine at a mean dose of 176 mg per day was superior to haloperidol for both positive and negative symptoms. These results are consistent with an open-label study by Remschmidt and colleagues (172). This group found that clozapine at a mean dose of 154 mg per day produced notable improvement in 27 of 36 (75%) adolescents with schizophrenia previously unresponsive to at least two trials of typical antipsychotics. 

Devanand DP, Sackeim HA, Brown RP, et al. A pilot study of haloperidol treatment of psychosis and behavioral disturbance in Alzheimer s disease. Arch Neuroi 1989 46 854-857. 

Aplasia cutis affected one of twin boys born to a mother with Graves disease, drug addiction, and psychosis, who had taken methimazole 40mg/day, propranolol, and haloperidol (with poor compliance) (96). 

Oosthuizen PP, Emsley RA, MaritzJS, et al. Incidence of tardive dyskinesia in first-episode psychosis patients treated with low-dose haloperidol. J Clin Psychiatry. 2003 64 1075-1080. 

Frequent symptoms of amphetamine withdrawal include excessive fatigue and depression. These may also occur nausea, vomiting, chills, cramps, headaches, and arrhythmia (a change in the rhythm of the heartbeat). A physician may prescribe antidepressants to help alleviate depression during amphetamine withdrawal. Also during withdrawal, if psychosis and/or hallucinations are experienced, treatment with chlorpromazine (Thorazine) or haloperidol (Haldol) may be necessary. Finally, ammonium chloride may be prescribed to more quickly remove amphetamines through the urine. 

The atypical neuroleptics also cause less sedation than the low-potency older neuroleptics such as chlorpromazine (Thorazine) and thioridazine (Mellaril), and fewer movement disorders than the older high-potency neuroleptics fluphenazine (Permitil, Prolixin) and haloperidol (Haldol). Although they often improve the symptoms of psychosis more effectively than the older drugs, the atypical neuroleptics are not without adverse side effects. 

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