LSD abuse

The combination of visual hallucinations, anxiety, panic, and depression are suggestive of use of a hallucinogen, such as lysergic acid diethylamide (LSD). Hallucinogens are compounds that, in nontoxic doses, cause distortions in perceptions without loss of consciousness. Agents traditionally classified as hallucinogens include LSD, mescaline, psilocybin, morning glory, nutmeg, and jimson weed. It is important to recognize, however, that hallucinations also may be produced by phencyclidine (PCP), cocaine, marijuana, and amphetamine derivatives such as methylenedioxymethamphetamine (MDMA, "Ecstasy").

The use of hallucinogens by adolescents peaked in 1979, when approximately 18% of high school seniors reported ever having tried one of these substances. In 1999, 14% of high school seniors reported having used a hallucinogen; 12% had used LSD, 3% PCP, and 8% MDMA. The mechanism of action of hallucinogens varies with the agent used. LSD is a sympathomimetic and, therefore, some of the earliest symptoms and signs (beginning within minutes of ingestion) are nausea, flushing, chills, dilated pupils, tachycardia, and hypertension. LSD is concentrated in the visual cortex and limbic and reticular activating systems where it binds to serotonin receptors, producing central nervous system effects within 15 to 20 minutes. Visual or auditory hallucinations are typical, and patients may experience  synesthesias, which represent sensory confusion in which colors are heard or smells seen. Some users experience a sense that they or others are aging rapidly; others develop paranoia, depression, panic, and anxiety. Severe toxicity may produce coma, respiratory arrest, hyperpyrexia, coagulopathy, or seizures. Long-term consequences of LSD use include flashbacks, personality changes, depressive symptoms, or psychosis. Despite these adverse effects, hallucinogens, including LSD, do not appear to produce physical dependence or a withdrawal state.

Intoxication with barbiturates, benzodiazepines, ethanol, or opiates produces sedation, not agitation, and is not associated with hallucinations. Furthermore, depressants (eg, barbiturates, benzodiazepines) and opiates cause miotic pupils, decreased body temperature, and decreased blood pressure, not signs of sympathetic stimulation, as seen in the adolescent in the vignette.

References:
Hurlbut KM, Joliff H, Hall AH, Fish SS, Rumack BH. LSD. In: Toll LL,
Hurlbut KM, eds. Poisindex System. Englewood, Co: Micromedex, Inc;
expires 12/2000. Available at: www.micromedex.com.
Johnston LD, Bachman JG, O'Malley PM, Schulenberg JE, Wallace J.
Monitoring the future: a continuing study of American youth. 1999.
Available at: http://www.monitoringthefuture.org.
Schwartz B, Alderman EM. Substances of abuse. Pediatr Rev. 1997;18:204-215