amphetamine psychosis and amphetamine-induced hallucinations

   Amphetamine is known under many names, including amp, crystal, phenylisopropylamine, speed, sulph, sulphate, and whizz. The name amphetamine is an acronym of alpha-methyl-phenyl-ethylamine. It is used to denote a subgroup of the CNS stimulants, as well as a prototype of that subgroup called racemic amphetamine, or simply amphetamine. As a group, amphetamines are classified as alkaloids of the phenethylamine group. They are closely related in chemical structure and pharmacology to other sympathomimetic amines such as nore-pinephrine and " ephedrine. Because of their stimulating effect, they are also known as 'uppers'. Amphetamine was synthesized for the first time in Germany in 1887 by the Romanian chemist Lazär Edeleanu (1861-1941), who gave it the name phenylisopropylamine. It was only after its resynthesis in 1927 by the British-American chemist Gordon Alles (who also introduced the name amphetamine) that serious attempts were made to devise a practical application. In 1932 the amphetamines were introduced in biomedicine in the form of Benzedrine, a decon-gestant nasal inhaler designed for individuals suffering from asthma, hay fever, or flu. During World War II, amphetamines were distributed to German, Italian, and Allied combat soldiers to increase wakefulness, alertness, endurance, and aggressiveness. Today the biomedical application of amphetamines is largely restricted to the treatment of neuropsychiatric disorders such as attention-deficit/hyperactivity disorder (ADHD) and narcolepsy. Amphetamines can be administered either orally, in the form of a tablet or a powder, or intravenously. The term 'bomber' is used to denote amphetamine powder that is swallowed wrapped in a cigarette paper. The principal central effects of amphetamine intoxication are increased attention, prolonged arousal, euphoria, a sense of increased energy and self-confidence, more rapid thought processes and decision-making, decreased appetite, weight loss, and a suppression of feelings of fatigue. These effects are attributed primarily to stimulation of the reticular formation. It has been reported that brief " psychotic reactions, lasting for up to several hours, can be provoked in any individual when a large enough dose of amphetamine is administered. In actual practice, however, such reactions are relatively rare. Most reports of amphetamine psychosis are related to the use of escalating doses of amphetamine and/or chronic high-dose binge administration. The mental condition characteristic of amphetamine psychosis can be described as a paranoid psychosis with delusions of reference and persecution, as well as hallucinations, occurring to a clear sensorium. The hallucinations and " illusions arising in the context of amphetamine psychosis tend to be " visual, " auditory, and occasionally " compound in nature, although "somatic, "tactile, and "olfactory hallucinations have also been reported. " Formicative hallucinations occurring in the context of amphetamine use are known as " crank bugs. The hallucinogenic and other psychotic effects of amphetamine intoxication are attributed primarily to overstimulation of the dopaminergic system. After the cessation of amphetamine consumption, these effects generally abate within several days to weeks. In combination with a vulnerability to psychosis, however, amphetamine use may result in prolonged and/or recurrent psychotic episodes, indistinguishable from those in individuals with a clinical diagnosis of"schizophrenia.

   References

   Kalant, O.J. (1973). The amphetamines: Toxicity and addiction. Second edition. Springfield, IL: Thomas.

   Rudgley, R. (1998). The encyclopaedia of psychoactive substances. London: Little, Brown and Company.

   Curran, C., Byrappa, N., McBride, A. (2004).

   Stimulant psychosis: Systematic review. British Journal of Psychiatry, 185, 196-204.