The role of inositol in the management of impulse control

  • Research type

    Research Study

  • Full title

    A short-term course of lithium carbonate or ebselen to test the effects of inositol monophosphate on impulsive action and decision-making in healthy (non-clinical) volunteers

  • IRAS ID

    244365

  • Contact name

    Robert D Rogers

  • Contact email

    r.rogers@bangor.ac.uk

  • Sponsor organisation

    Bangor University

  • Duration of Study in the UK

    2 years, 11 months, 28 days

  • Research summary

    Summary of research
    Impulsive behaviour is a prominent feature of alcohol or drug misuse disorders as well as bipolar disorder. It is strongly associated with relapse and poor patient outcomes. Bipolar disorder patients are commonly treated with the mood stabiliser, lithium carbonate. Lithium is effective in treating acute mania and as a longer-term maintenance therapy. It has also been shown to have helpful effects on impulsive behaviours including aggression and hazardous gambling. However, long-term use of lithium is associated with renal toxicity and requires careful monitoring of blood levels of the drug. This represents a major limitation to the use of lithium in clinical practice. At a basic level, lithium’s therapeutic effects seem to involve the inhibition of a brain chemical called inositol. Therefore, finding drugs that work in the same way but which are more easily tolerated by patients may offer a route to finding safer ways to address impulsivity in psychiatric disorders. Recently, we found preliminary evidence that inositol inhibition, achieved by an anti-inflammatory drug called ebselen, produces anti-impulsive effects in healthy volunteers. Ebselen was originally developed for the treatment of stroke and appears safer and better tolerated than lithium in the clinic. However, at the current time, we do know how inositol inhibition alters the cognitive and emotional aspects of impulsive behaviour in human adults. Accordingly, we will use an experimental medicine approach to recruit healthy volunteers and test whether inositol inhibition produced by short-term treatments with either lithium or ebselen alter different aspects of impulsive behaviour and whether these effects are more marked in individuals with stronger impulsive traits than individuals with weaker impulsive traits. Doing so will help us to understand the therapeutic potential of inositol inhibition.

    Summary of Results
    Impulsivity is a broad transdiagnostic risk factor across a variety of psychological disorders and addictions and is strongly associated with relapse and poor treatment outcomes. Here, we sought to test the hypothesis that the major expressions of impulsivity can be moderated by the IMPase inhibitor, ebselen, in healthy (non-clinical) adults. There were no substantive changes in any outcome measure following treatment with ebselen compared with placebo, or any substantive evidence that treatment effects were stronger or weaker in high-trait impulsive individuals compared with low-trait individuals. These findings throw some doubt on the hypothesis that impulsivity is are sensitive to the modulation of myo-inositol activity by treatment with the IMPase inhibitor, ebselen.

  • REC name

    Wales REC 2

  • REC reference

    19/WA/0349

  • Date of REC Opinion

    13 Jan 2020

  • REC opinion

    Further Information Favourable Opinion