Contact Information

Department of Psychology
California State University San Marcos
333 S. Twin Oaks Valley Road
San Marcos, CA 92096
United States of America

Office (760) 750-4183
Fax (760) 750-3418

Research Keywords
  • Drug Abuse; Plasticity; Tolerance; Dependence; Sensitization
Membership Information

Membership Category:
Research Scientists

Member Since: 2001


Keith A. Trujillo, Ph.D.

Keith A. Trujillo, Ph.D.


Ph.D. University of California, Irvine

Research Statement

Dr. Trujillo is a psychopharmacologist and behavioral neuroscientist with wide-ranging interests in the brain and behavior. He has performed research on brain mechanisms of reward, on drug-induced changes in the brain and behavior, including tolerance, dependence and sensitization, and on a variety of drugs of abuse, including opiates, psychomotor stimulants and dissociatives. He has also performed research on schizophrenia and major depression. His research has been funded by the National Institute on Drug Abuse (NIDA), the National Institute of Mental Health (NIMH), the National Institute of General Medical Sciences (NIGMS) and the National Alliance for Research on Schizophrenia and Depression (NARSAD).

About Me

Keith Trujillo is Professor of Psychology and Associate Director of the Office for Biomedical Research and Training at California State University San Marcos. He received an Associate of Arts degree in Biological Sciences from Shasta College, Bachelors degrees in Biological Sciences, Psychology and Chemistry from California State University, Chico, and a Ph.D. in Pharmacology and Toxicology from the University of California, Irvine. Following completion of his doctorate he worked as a Postdoctoral Fellow and a Research Investigator at The University of Michigan. Keith is a neuroscientist and psychopharmacologist with a longstanding interest in the neural basis of drug abuse and addiction. His publication with Dr. Huda Akil on the discovery of the role of the neurotransmitter glutamate in drug tolerance and dependence has been ranked as one of the most highly cited papers in the field of pain and analgesia and has been named a “citation classic”. In addition to his laboratory research, Keith has strong interests in Latino issues, in increasing diversity in science and academia, and in training the next generation of scientists. He was an Expert Panelist for the National Strategic Plan on Hispanic Drug Abuse Research and received the National Award of Excellence in Mentorship from the National Hispanic Science Network in 2005.

View Curriculum Vitae

Recent Publications

Mendez, I.A. and Trujillo, K.A. (2008). NMDA receptor antagonists inhibit locomotor sensitization and analgesic tolerance in rats. Psychopharmacology, 196, 497-509.

Trujillo, K.A., Zamora, J.J. and Warmoth, K.P. (2008). Increased response to ketamine following treatment at long intervals: Implications for intermittent use. Biological Psychiatry, 63, 178-183.

Trujillo, K.A., Castañeda, E., Martínez, D. and González, G. (2006). Biological research on drug abuse and addiction in Hispanics: Current status and future directions. Drug and Alcohol Dependence, 84 (Suppl), S17-S28.

Trujillo, K.A., Kubota, K.S. and Warmoth, K.P. (2004). Continuous administration of opioids produces locomotor sensitization. Pharmacology Biochemistry & Behavior, 79, 661-669.