Drug-induced nightmares.
OBJECTIVE
To compile and assess the English-language literature on drug-induced nightmares, excluding nightmares secondary to drug withdrawal or drug-associated night terrors.


METHODS
Published articles, letters, case reports, and abstracts in English were identified by MEDLINE (1966-May 1998) searches using the search term nightmares, chemically induced. Additional articles were obtained from bibliographies of retrieved articles.


METHODS
All case reports of drug-induced nightmares were evaluated using the Naranjo algorithm for causality. Clinical studies of drugs that reported nightmares as an adverse effect were assessed for frequency of occurrence.


RESULTS
Nightmares, defined as nocturnal episodes of intense anxiety and fear associated with a vivid, emotionally charged dream experience, are generally classified as a parasomnia. Possible pharmacologic mechanisms for drug-induced nightmares, such as REM suppression and dopamine receptor stimulation, are reviewed. However, the vast majority of therapeutic agents implicated in causing nightmares have no obvious pharmacologic mechanism.


CONCLUSIONS
Assessing causality with an event such as a nightmare is difficult because of the high incidence of nightmares in the healthy population. Using qualitative, quantitative, and possible pharmacologic mechanism criteria, it appears that sedative/hypnotics, beta-blockers, and amphetamines are the therapeutic modalities most frequently associated with nightmares. These drug classes have a plausible pharmacologic mechanism to explain this effect. Dopamine agonists also have evidence of causality, with dopamine receptor stimulation as a possible pharmacologic mechanism.
Thompson
D F
DF
Department of Pharmacy Practice, School of Pharmacy, Southwestern Oklahoma State University, Oklahoma City 73102, USA. thompsd@swosu.edu
Pierce
D R
DR
D000319:Adrenergic beta-Antagonists / Q000009:adverse effects; D000662:Amphetamines / Q000009:adverse effects; D004325:Dreams; D006801:Humans; D006993:Hypnotics and Sedatives / Q000009:adverse effects; D016239:MEDLINE; D012893:Sleep Wake Disorders / Q000139:chemically induced*; D012895:Sleep, REM / Q000187:drug effects