Lysergic Acid Diethylamide:
Lysergic acid diethylamide, ﬁrst synthesised by Albert Hoffman in 1938 and popularly known as ‘ acid’, is a powerful hallucinogen. It related to the psychedelic compounds found in the ‘morning glory’ seeds, the lysergic acid amides. As little as 100 μg of LSD is sufﬁcient to produce behavioural effects in man. LSD presumably produces its effects by an action on the 5-HT levels in brain.
Although tolerance as well as psychological dependence can occur with LSD use, no physical dependence or withdrawal syndrome is reported. A common pattern of LSD use is a trip (occasional use followed by a long period of abstinence).
The characteristic features of acute LSD intoxication are perceptual changes occurring in a clear consciousness. These perceptual changes include depersonalisation, derealisation, intensiﬁcation of perceptions, synaesthesiac (for example, colours are heard, and sounds are felt), illusions, and hallucinations.
In addition, features suggestive of autonomic hyperactivity, such as pupillary dilatation, tachycardia, sweating, tremors, incoordination, palpitations, raised temperature, piloerection and giddiness, can also be present. These changes are usually associated with marked anxiety and/or depression, though euphoria is more common in small doses. Persecutory and referential ideation may also occur.
Sometimes, acute LSD intoxication presents with an acute panic reaction, known as a bad trip, in which the individual experiences a loss of control over himself. The recovery usually occurs within 8-12 hours of the last dose. Rarely, the intoxication is severe enough to produce an acute psychotic episode resembling a schizophreniform psychosis.
No withdrawal syndrome has described with LSD use. However, sometimes, there is a spontaneous recurrence of the LSD use experience in a drug free state. Described as a ﬂashback, it usually occurs weeks to months after the last experience. Such episodes are often induce by stress, fatigue, alcohol intake, severe physical illness or marihuana intoxication.
Long-term LSD use is not a common phenomenon. The complications of chronic LSD use include psychiatric symptoms (anxiety, depression, psychosis or visual hallucinosis) and occasionally foetal abnormalities.
The treatment of acute LSD intoxication consists of symptomatic management with antianxiety, antidepressant or antipsychotic medication, along with supportive psychotherapy.