Coma Blisters, Peripheral Neuropathy, and Amitriptyline Overdose: A Brief Report Sheilagh Maguiness, 1 Lyn Guenther, 2 and David Shum, 3 Abstract Background: Coma blisters are most commonly associated with barbiturate and benzodiazepine overdose; however, they have also been described in association with many other substances, including amitriptyline. Objective: To review the literature on the clinical manifestations of coma blisters in the setting of amitriptyline overdose. Methods: Case report and literature review. Results: Coma blisters in association with amitriptyline overdose have rarely been documented in the literature. Of the few reported cases, peripheral neuropathy has been present two including our case report) out of four times. Conclusion: Amitriptyline is known to impair endothelial cell tight junction integrity. Thus, individuals with amitriptyline overdose may be predisposed to microvascular damage during the compression imposed from a comatose state. This may help to explain the tendency for patients to present with the interesting triad of coma, blisters, and neuropathy. Sommaire AnteÂceÂdents: Les cloques qui apparaissent durant le coma sont souvent associe Âesa Á une overdose de barbiturique ou de benzodiaze Âpine, mais peuvent e Ãtre lie Âes e Âgalement a Á beaucoup d'autres substances, notamment l'amitriptyline. Objectif: Passer en revue les publications sur la manifestation clinique des cloques en pre Âsence d'une overdose d'amitriptyline. MeÂthodes :E  tude de cas et examen des publications. ReÂsultats: Les publications scienti®ques traitent rarement des cloques apparaissant durant le coma qui sont lie Âes a Á une overdose d'amitriptyline. Parmi les quelques cas rapporte Âs, deux fois sur quatre dont notre rapport de cas), il y avait pre Âsence de neu- ropathie  pe Âriphe Ârique. Conclusion: L'amitriptyline est connue pour endommager l'inte Âgrite  des jonctions serre Âes des cellules endothe Âliales. Par conse Âquent, les personnes ayant rec Ëu une overdose d'amitriptyline seraient sujettes aux affections microvasculaires durant la compression produite par leur e Âtat comateux. B listers in the comatose patient were ®rst reported by Villaret in the early 1930's, 1 but were described as early as the 1800s in soldiers of the French Revolution who had been exposed to carbon monoxide. 2 Since that time, blisters in the comatose patient have been well described in association with overdose of medications, in particular with barbiturates and benzodiazepines. Coma blisters are usually self-limited eruptions and occur in about 5% of hospitalized patients in the comatose state. 3 Most case reports describe the patients as developing tense, ¯uid-®lled bullae after the appearance of an ery- thematous plaque. The exact etiology of the blisters is still controversial. Some believe that pressure leading to tissue anoxia may be causative, 4±7 however, the blisters often form in nondependent sites. The role of overdose is DOI: 10.1007/s10227-001-0132-8 J Cutan Med Surg 2002; 438±441 1 University of Western Ontario, London, Ontario, Canada 2 Department of Dermatology, University of Western Ontario, London, Ontario, Canada 3 Department of Pathology, University of Western Ontario, London, Ontario, Canada Correspondence to: Lyn Guenther, MD, 835 Richmond Street, London, Ontario N6A 3H7, Canada. E-mail: dgue@uwo.ca Online publication 16 July 2002 438