Rivastigmine for treatment resistant Post Traumatic stress disorder

To the Editor

We report positive findings from an open trial of the treatment of chronic and severe post-traumatic stress disorder (PTSD) with rivastigmine (RVST), an acetylcholinesterase inhibitor approved for the treatment of dementia. The decision to add RVST stemmed from a published report of significant improvement in PTSD symptoms in three veterans of the Iran–Iraq war who had chronic and severe PTSD (Bordbar and Talaei, 2012). RVST was prescribed at doses of up to 12 mg orally or 13.3 mg transdermally to 44 serving or former police and emergency services personnel with Diagnostic and Statistical Manual of Mental Disorders 5 (DSM-5) PTSD, present for an average of 9.8 years and who had not responded to treatment with psychotherapy and at least two forms of psychotropic medication. Most had a pattern of avoidant behaviour, but were more distressed by intrusive memories and persistent anxiety (29/44, 66%) or irritability (30/44, 68%). All of the patients were assessed to be able to give informed consent to the trial of treatment. The off-label prescription of RVST was justified by the positive effect observed in the first few patients who received the treatment, and the degree of distress and disability experienced by all of these patients. Outcome was assessed from subjective improvement in the domains of avoidance, intrusive memories and arousal symptoms, clinician rating using a Global Clinical Impression and the use of other medication. Seven patients (16%) discontinued RVST because of adverse effects. The remaining 37 patients took the drug for an average of 26.5 weeks (range 4–37 weeks). Of those, 33 (89%) reported subjective benefit, and the Global Clinical Impression was that 30 (81%) of those who continued the treatment improved. A reduction in the frequency of intrusive memories was reported in 34 patients (77%), and an improvement in arousal symptoms, including anxiety, irritability, hyper-vigilance and the frequency of nightmares, was reported in 33 patients (75%). Being involved in workplace litigation did not influence the likelihood of continuing the treatment, or subjective or objective improvement. A reduction in the use of other medications, including antidepressants, mood stabilisers and sympathoplegic agents, was possible in 18 (41%) patients taking RVST, many of whom had been taking those medications long term. Limitations of this study include the lack of a control group and the potential for a placebo effect on both the patients and the treating doctor. Nevertheless, the results from this large case series provide support for a further trial of RVST in other groups of patients with treatment resistant PTSD.