Forensic Toxicol
DOI 10.1007/s11419-009-0079-9

SHORT COMMUNICATION

Capsaicin, an active ingredient in pepper sprays, increases the lethality
of cocaine
John E. Mendelson · Bryan K. Tolliver
Kevin L. Delucchi · Matthew J. Baggott · Keith Flower
C. Wilson Harris · Gantt P. Galloway · Paul Berger

Received: 15 June 2009 / Accepted: 17 July 2009
© Japanese Association of Forensic Toxicology and Springer 2009

Abstract Since 1992, California police have been using
pepper sprays containing oleoresin capsicum (OC) as a
nonlethal method to subdue delirious or violent individuals. Capsaicin is a primary ingredient in OC spray.
From January 1993 to June 1995, at least 20 deaths in
California were associated with OC and stimulant drug
(cocaine, amphetamines, or ephedrines) exposure. Based
on this background, we hypothesized a direct potentiation of cocaine toxicity by capsaicin. We performed
animal experiments and also reviewed human data
involving capsaicin and stimulants. The lethal effects of
capsaicin administered with cocaine (both compounds
administered intraperitoneally) were assessed in 14
groups of 20–40 male mice. Capsaicin at 10 mg/kg
increased the lethality of cocaine in mice dosed at 60 mg/
kg from 13% to 53% (P < 0.01) and for cocaine at 75 mg/
kg from 53% to 90% (P < 0.001). Data from 26 autopsy
and police reports from incidents in which death occurred

J.E. Mendelson (*) · M.J. Baggott · K. Flower · C.W. Harris ·
G.P. Galloway
Addiction and Pharmacology Research Laboratory, California
Pacific Medical Center Research Institute, St. Luke’s Hospital,
3555 Cesar Chavez Street, San Francisco, CA 94110, USA
e-mail: john.mendelson@cpmcri.org
B.K. Tolliver
Department of Psychiatry, Medical University of South
Carolina, Charleston, SC, USA
K.L. Delucchi
Drug Dependence Research Center, Department of Psychiatry,
Langley Porter Psychiatric Institute, University of California,
San Francisco, CA, USA
P. Berger
Department of Psychiatry, Oregon Health and Science
University, Portland, OR, USA

after OC exposure were retrospectively analyzed for
demographics, ethnicity, underlying disease, cause of
death, and toxicology. All human deaths occurred in
delirious and combative males, and 79% of these deaths
occurred 1 h or less after OC exposure. Data indicated
the presence of stimulants including cocaine in as many
as 19 out of 26 deaths: 9 involved methamphetamine, 6
cocaine, 3 methamphetamine plus cocaine, and 1 pseudoephedrine. The animal experiments together with the
human retrospective analysis support the idea that
exposure to OC spray in cocaine-intoxicated individuals
potentiates cocaine lethality.
Keywords Capsaicin · Riot control · Pepper spray ·
Cocaine · Amphetamines · Lethality

Introduction
In the 1980s, sprays containing capsaicin, an extract of
Capsicum spp., were developed as animal repellents by
Canadian Park rangers (for grizzly and black bears) and
later adopted by postal workers and meter readers (for
dogs). Law enforcement agencies, seeking effective and
less-than-lethal methods to control violent and delirious
people, have been using these sprays as weapons since
1992. These weapons are variously known as pepper
spray, pepper gas, pepper mace, or oleoresin capsaicin
(OC) spray and are used by law enforcement agencies
and sold to the general public for personal safety [1].
For the police and the public, pepper sprays offer a safe
and humane alternative to batons and firearms. By
June 1995, California police officers had used pepper
sprays nearly 16 000 times (about 24 times per day).
Around this time, reports emerged of a number of

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