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Antibiotics Found Effective in Schizophrenia

Tetracyclines help treat psychosis as well as tick-borne disorders.

A controlled clinical trial was just published in the psychiatric literature, showing that minocycline is effective in treating negative symptoms in early phase schizophrenia. A prior pilot study, published in 2010 in the Journal of Clinical Psychiatry, also showed that minocycline was effective in schizophrenia, helping executive functioning such as working memory. The authors postulate that the mechanism of action of minocycline would include affecting glutamate pathways in the central nervous system, blocking nitric oxide-induced neurotoxicity, or inhibiting microglial activation in the brain, causing inflammation. All of these are reasonable potential mechanisms of action. Neither author discusses the obvious fact however that minocycline is a tetracycline antibiotic and that it may be treating an occult infection. Have infections ever been reported to cause schizophrenia?

Lyme disease causes a wide range of psychiatric manifestations. Published research has shown a higher prevalence of antibodies to Borrelia burgdorferi in psychiatric patients than in healthy subjects. There is also a known geographic correlation of schizophrenia with ticks and tick-borne encephalitis, with peer reviewed literature showing an association of Lyme disease with schizophrenia. Other tick-borne infections, such as Bartonella (cat scratch disease) have also been reported to cause neurological and neurocognitive dysfunction, as well as causing agitation, panic disorder and treatment resistant depression. Minocycline, as well as other tetracycline antibiotics like doxycycline, are well known treatments for neurological manifestations of Lyme disease and associated co-infections like Bartonella. It is therefore plausible that a certain number of cases of severe psychiatric presentations are due to underlying infections, especially since Lyme disease is the number one spreading vector borne infection in the world.

I have seen several patients who came to my medical clinic with a diagnosis of schizophrenia, on anti-psychotic medications like Risperdal. Upon further testing, their Western Blots returned positive for exposure to Borrelia burgdorferi, the agent of Lyme disease. They were given doxycycline (a similar tetracycline antibiotic), and their psychotic symptoms and cognition improved significantly. Working with their psychiatrist, we were able to reduce, and in some cases eliminate, all of their antipsychotic medication. They remained clinically stable as long as they remained on antibiotics. Their psychiatric symptoms returned once they were no longer being treated for Lyme and associated tick-borne disorders, as these organisms have been shown to be able to establish a persistent infection in the body.

When should we suspect Lyme disease as a potential etiological co-factor in psychiatric symptoms? Lyme disease is a multisystemic illness. If a patient presents with a symptom complex that comes and goes with good and bad days, with associated fevers, sweats and chills, fatigue, migratory joint and muscle pain, migratory neuralgias with tingling, numbness and burning sensations, a stiff neck and headache, memory and concentration problems, a sleep disorder and associated psychiatric symptoms (that may or may not be of recent onset), then we should suspect Lyme disease and associated co-infections. Have these patients fill out a Lyme screening questionnaire that we developed in my medical office. Among 100 patients who filled out this form, a score above 46 was associated with a high probability of a tick-borne disorder. In that case, blood testing should be performed through a reliable laboratory to look for Lyme and co-infections, including Babesia and Bartonella, which can also significantly increase underlying symptomatology.

Lyme disease is a major cause of psychiatric symptoms. Psychiatric case reports, as reported by psychiatrist Dr Brian Fallon, have linked Lyme disease to paranoia, thought disorders, delusions with psychosis, schizophrenia, with or without visual, auditory or olfactory hallucinations, depression, panic attacks and anxiety, obsessive compulsive disorder, anorexia, mood lability with violent outbursts, mania, personality changes, catatonia and dementia. Other psychiatric disorders in adults due to Lyme disease include atypical bipolar disorder, depersonalization/derealization, conversion disorders, somatization disorders, atypical psychoses, schizoaffective disorder and intermittent explosive disorders. In children and adolescents, Lyme disease can also mimic Specific or Pervasive Developmental Delays, Attention-Deficit Disorder (Inattentive subtype), oppositional defiant disorder and mood disorders, obsessive compulsive disorder (OCD), anorexia, Tourette’s syndrome, and pseudo-psychotic disorders. The take home message: Lyme is the “great imitator”. Don’t exclude Lyme disease and associated infections as a possible underlying cause of psychiatric symptoms, and don’t assume that a positive response to an antibiotic like minocycline is not treating an underlying infection.

Dr Richard Horowitz

Scientific references:

Liu, F., Guo, X., Wu, R., et al. (2014). Minocycline supplementation for treatment of negative symptoms in early-phase schizophrenia: A double blind, randomized, controlled trial. Schizophr Res. Published on line:

Levkovita, Y., Mendlovich, S., Riwkes, S., et al. (2010). A double-blind, randomized study of minocycline for the treatment of negative and cognitive symptoms in early-phase schizophrenia. J. Clin Psychiatry 71(2):138-49.

Fallon, B.A., & Nields, J.A. (1994). Lyme disease: A neuropsychiatric illness. Am J Psychiatry 151(11):1571-83.

Fallon, B.A., Kochevar, J.M., Gaito, A., & Nields, J.A. (1998). The underdiagnosis of neuropsychiatric Lyme disease in children and adults. Psychiatric Clinics of North America 21: 693-703.

Hajek, T., Paskova, B., Janovska, D., et al. (2002). Higher prevalence of antibodies to Borrelia burgdorferi in psychiatric patients than in healthy subjects.
Am J Psychiatry 159:297-301.

Hess, A., Buchmann, J., Zettl, U.K., Henschel, S., Schlaefke, D., Grau, G., & Benecke, R. (1999). Borrelia burgdorferi central nervous system infection presenting as an organic schizophrenialike disorder. Biol Psychiatry 45(6):795.

Brown, J.S. Jr. (1994). Geographic correlation of schizophrenia to ticks and tick-borne encephalitis. Schizophr Bull; 20(4):755-75

Breitschwerdt, E.B., Maggi, R.G., Nicholson, W.L., Cherry, N.A., & Woods, C.W. Bartonella sp. bacteremia in patients with neurological and neurocognitive dysfunction. Journal of Clinical Microbiology. 46(9):2856–2861.

Schaller, J.L., Burkland, G.A., & Langhoff, P.J. (2007). Do bartonella infections cause agitation, panic disorder, and treatment-resistant depression? MedGenMed. 9(3):54.

Fallon, B.A., Levin, E.S., Schweitzer, P.J., & Hardesty, D. (2010). Inflammation and central nervous system Lyme disease. Neurobiology of Disease 37: 534-541

Sherr, V.T. (2000). Panic attacks may reveal previously unsuspected chronic disseminated Lyme disease. J. Psychiatric Practice, 6:352-356.

Benke, T., Gasse, T., Hittmair-Delazer, M., & Schmutzhard, E. (1995). Lyme encephalopathy: Long-term neuropsychological deficits years after acute neuroborreliosis. Acta Neurol Scand. 91(5):353-7;

Nicolson G., & Haier, J. (2009). Role of chronic bacterial and viral infections in neurodegenerative, neurobehavioral, psychiatric, autoimmune and fatiguing illnesses: Part I. BJMP 2(4) 20-28.

Krause. P.J. et al. (1996). Concurrent Lyme disease and babesiosis. Evidence for increased severity and duration of illness. JAMA 275(21):1657-1660.

Preac-Mursic, V. et al. (1989). Survival of Borrelia burgdorferi in antibiotically treated patients with Lyme borreliosis. Infection 17:355-359

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