Stimulant psychosis

Stimulants induce both tolerance and sensitization to their behavioral effects. Tolerance develops to the anorectic and euphoric effects of stimulants (Schuster 1981) however, chronic intermittent use of low doses of stimulants delays the development of tolerance. With the doses commonly used in clinical practice, patients treated for narcolepsy or for depressive or apathetic states find that the stimulant properties usually persist without development of tolerance however, the persistence of antidepressant effects remains a matter of controversy. Sensitization has been linked to the development of amphetamine-induced psychosis (Yui et al. 1999). Sensitization to the induction of psychosis is suggested because psychosis is induced by progressively lower doses and shorter periods of consumption of amphetamine following repeated use over time (Sato 1986). Sensitization for amphetamine-induced psychosis may persist despite long periods of abstinence. 

The development of psychosis is the most striking clinical characteristic of high-dose stimulant abuse. The amphetamines, methylphenidate, and phen-metrazine all produce psychosis (Ellinwood et al. 1973 Harris and Batki 2000 Iversen et al. 1978 Lucas and Weiss 1971 McCormick and McNeil 1962). 

King GR, Ellinwood EH Amphetamines and other stimulants, in Substance Abuse A Comprehensive Textbook, 3rd Edition. Edited by Lowinson JH, Ruiz P, Mill-man RB, et al. Baltimore, MD, Williams Wilkins, 1997, pp 207—233 Klawans HE, Margolin Dl Amphetamine-induced dopaminergic hypersensitivity in guinea pigs implications in psychosis and human movement disorders. Arch Gen Psychiatry 32 725—732, 1975... 

Ellinwood, E.H., Jr., and Kilbey. M.M. Chronic stimulant intoxication models of psychosis. In Hanin, I., and Usdin, E., eds. Animal Models in Psychiatry and Neurology. New York Pergamon Press, 1977. pp. 61-74. 

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. 

Yui, K., Goto, K., Ikemoto, S. et al. Neurobiological basis of relapse prediction in stimulant-induced psychosis and schizophrenia the role of sensitization. Mol. Psychiatry. 4 512, 1999. 

Phencyclidine (PCP) psychosis faithfully masquerades as schizophrenia, though some say it resembles mania. PCP is discovered to block NMDA subtypes of glutamate receptors. Glycine and cycloserine, which stimulate NMDA receptors, are antipsychotic. 

Toxic psychosis Several monoamine stimulants including cocaine are known to produce a temporary or even a lasting psychotic state after heavy use. Reviews of numerous clinical case reports have shown amphetamine to produce a chronic psychotic state, sometimes persisting for months after cessation. There appears to be a sensitization effect in this regard, because after recovery, psychotic states may recur with minimal use of amphetamine or alcohol. When compared to schizophrenic patients, people with amphetamine-induced psychosis demonstrate fewer negative symptoms (Boutros and Bowers 1996). 

As would be expected, khat overuse produces symptoms similar to those of other monoamine stimulants, such as cocaine or amphetamine, including signs of sympathetic overarousal. In the extreme this can involve a toxic psychosis. Disorders more frequently associated with chronic khat use in males are headaches, anorexia, insomnia, constipation, and respiratory illnesses (Kennedy et al. 1983). Females report higher incidences of acute gastritis, jaundice, bronchitis and hepatic diseases. Also, cathinone has toxic reproductive effects in humans and experimental animals (Islam et al. 1990). It decreases sperm count and motility, and increases the number of abnormal sperm cells. It also decreases plasma testosterone in rats. 

In the aftermath of World War II, problems with amphetamine abuse began to arise. An epidemic of amphetamine abuse and related cases of amphetamine-induced psychosis arose first in Japan and later in the United States. Since that time, use of amphetamines and other stimulants has been greatly curtailed and as a class are more tightly regulated than virtually any other psychotropic agents, with the exception of narcotic analgesics. 

The prescribing physician should be notified immediately if tics or psychosis (usually paranoia) develop. The medication should always be stopped when psychosis occurs. We once said the same about tics, but recent research suggests that stimulants may not worsen tics. Methylphenidate is now available in a controlled-release preparation (Concerta), which can be prescribed once daily. One key advantage to once-daily dosing is not pharmacological, but rather that it avoids the stigma children may experience when they need to go to the school nurse s office to receive their afternoon dose. Focalin is the active isomer of methylphenidate. 

The side effects of pemoline are similar to other stimulants but milder. The most common side effects are loss of appetite, nausea, and insomnia. Infrequent side effects include headache, dizziness, changes in mood, increases in blood pressure or pulse, and psychosis. 

Less frequent side effects of stimulants include euphoria, nervousness, irritability, headache, involuntary movements (tics), increased heart rate, and psychosis. If psychosis or tics develop, the patient s doctor should be notified immediately, and the medication should be stopped. Other side effects should also be reported and may necessitate a medication change. 

Attention deficit hyperactivity disorder (ADHD) For the treatment of ADHD in patients 6 years of age and older. Dexmethylphenidate is indicated as an integral part of a total treatment program for ADHD that may include other measures (eg, psychological, educational, social) for patients with this syndrome. Drug treatment may not be indicated for all patients. Stimulants are not intended for use in the patient who exhibits symptoms secondary to environmental factors or other primary psychiatric disorders, including psychosis. 

CNS CNS effects including convulsions, increased intracranial pressure, and toxic psychosis have been reported with nalidixic acid therapy. Convulsive seizures have been reported with other drugs in this class. Quinolones also may cause CNS stimulation, which may lead to confusion, hallucinations, light-headedness, restlessness, and tremor. Therefore, use nalidixic acid with caution in patients with known or suspected CNS disorders (eg, cerebral arteriosclerosis, epilepsy) or other factors that predispose to seizures. If these reactions occur in patients receiving... 

Seizures Increased intracranial pressure, convulsions, and toxic psychosis have occurred. CNS stimulation also may occur and may lead to tremor, restlessness, lightheadedness, confusion, dizziness, depression, hallucinations, and rarely, suicidal thoughts or acts. 

Mypotenslon, abdominal distress, CNS stimulation (monia/ psychosis In predlsposeo Individuols)... 

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-... 

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