Research Article| Volume 28, ISSUE 8, P728-732, October 15, 1990

Tryptophan treatment of aggressive psychiatric inpatients

      This paper is only available as a PDF. To read, Please Download here.


      This double-blind, placebo-controlled study tested the effectiveness of tryptophan (TRP) in the treatment of aggressive psychiatric inpatients. After a baseline observation period of 1 month, patients were randomly assigned to treatment either with TRP (up to 6 g/day) or with placebo. There were 10 subjects in each treatment group. These treatments were administered for 25–35 days, after which the patients were observed for 1 month. Throughout this study, patients were receiving other medications. Injections of antipsychotics and sedatives were administered as needed to control agitated or violent behavior. Blood levels of TRP and other large neutral amino acids were obtained repeatedly, and ratios between TRP and other amino acids were computed. These analyses confirmed significant increases of TRP ratios in TRP-treated patients. TRP treatment had no effect on the number of violent incidents, but it significantly reduced the need for injections of antipsychotics and sedatives. The study thus provided indirect support for beneficial effects of TRP in aggressive psychiatric inpatients.


        • Bidlingmeyer B.A.
        • Cohen S.A.
        • Tarvin T.L.
        Rapid analysis of amino acids using pre-column derivitization.
        J Chromatogr. 1984; 336: 93-104
        • Bioulac B.
        • Benezich M.
        • Renaud B.
        • Noel B.
        • Roche D.
        Serotonergic function in the 47, XYY syndrome.
        Biol Psychiatry. 1980; 15: 917-923
        • Blevins W.L.
        • Hertzman P.
        • Ting M.
        • et al.
        Fosinophilia-myalgia syndrome-New Mexico.
        JAMA. 1989; 262: 3116
        • Branchey M.
        • Branchey M.
        • Shaw S.
        • Lieber C.S.
        Depression, suicide, and aggression in alcoholics and their relationship to plasma amino acids.
        Psychiatry Res. 1984; 12: 219-226
        • Brown G.L.
        • Goodwin F.K.
        • Ballenger J.C.
        • Goyer P.F.
        • Major L.F.
        Aggression in humans correlates with cerebrospinal fluid amine metabolites.
        Psychiatry Res. 1979; 1: 131-139
        • Coccaro E.F.
        • Siever L.J.
        • Klar H.M.
        • et al.
        Serotonergic studies in patients with affective and personality disorders.
        Arch Gen Psychiatry. 1989; 46: 587-599
        • Fernstrom J.D.
        • Wurtman R.J.
        Brain serotonin content: Physiological regulation by plasma neutral amino acids.
        Science. 1972; 178: 414-416
        • Guy W.
        ECDEU Assessment Manual for Psychopharmacology.
        National Institute of Mental Health, Rockville, MD1976
        • Linnoila M.
        • Virkkunen M.
        • Scheinin M.
        • Nuutila A.
        • Rimon R.
        • Goodwin F.K.
        Low cerebrospinal fluid 5-hydroxyindoleacetic acid concentration differentiates impulsive from nonimpulsive violent behavior.
        Life Sci. 1983; 33: 2609-2614
        • Morand C.
        • Young S.N.
        • Ervin F.R.
        Clinical response of aggressive schizophrenics to oral tryptophan.
        Biol Psychiatry. 1983; 18: 575-578
        • O'Neil M.
        • Page N.
        • Adkins W.N.
        Tryptophan-trazodone treatment of aggressive behavior.
        Lancet. 1986; ii: 859-860
        • Richardson M.A.
        • Suckow R.
        • Whittaker R.
        • et al.
        Boulton A.A. Jurio A.V. Downer R.G.M. Phenylalanine, phenylethylamine and tardive dyskinesia in psychiatric patients in trace amines: Comparative and clinical neurobiology. Humana Press, Clifton, NJ1988: 409-422
        • Slutsker L.
        • Hoesly F.C.
        • Miller L.
        • Williams L.P.
        • Watson J.C.
        Eosinophilia-myalgia syndrome associated with exposure to tryptophan from a single manufacturer.
        JAMA. 1990; 264: 213-217
        • Virkkunen M.
        • De Jong J.
        • Bartko J.
        • Goodwin F.K.
        • Linnoila M.
        Relationship of psychobiological variables to recidivism in violent offenders and impulsive fire setters.
        Arch Gen Psychiatry. 1989; 46: 600-603