We have reviewed the international literature regarding pharmacological (drug) and natural product (dietary supplementation) treatment trials in the field. A total of seven trials meeting our inclusion criteria were identified. There is little evidence of beneficial effects of either pharmacological or natural product treatments. However, few trials have been conducted and those that have are small, meaning that possible beneficial effects of some therapies cannot be ruled out.
Why is this review important?
Self-harm (SH), which includes intentional self-poisoning/overdose and self-injury, is a major problem in many countries and is strongly linked with suicide. It is therefore important that effective treatments for SH patients are developed. Whilst there has been an increase in the use of psychosocial interventions for SH in adults (which is the focus of a separate review), drug treatments are frequently used in clinical practice. It is therefore important to assess the evidence for their effectiveness.
Who will be interested in this review?
Hospital administrators (e.g. service providers), health policy officers and third party payers (e.g. health insurers), clinicians working with patients who engage in SH, patients themselves, and their relatives.
What questions does this review aim to answer?
This review is an update of a previous Cochrane Review from 2015 which found little evidence of beneficial effects of drug treatments on repetition of SH. This updated aims to further evaluate the evidence for effectiveness of drugs and natural products for patients who engage in SH with a broader range of outcomes.
Which studies were included in the review?
To be included in the review, studies had to be randomised controlled trials of drug treatments for adults who had recently engaged in SH.
What does the evidence from the review tell us?
There is currently no clear evidence for the effectiveness of antidepressants, antipsychotics, mood stabilisers, or natural products in preventing repetition of SH.
What should happen next?
We recommend further trials of drugs for SH patients, possibly in combination with psychological treatment.
Given the low or very low quality of the available evidence, and the small number of trials identified, there is only uncertain evidence regarding pharmacological interventions in patients who engage in SH. More and larger trials of pharmacotherapy are required, preferably using newer agents. These might include evaluation of newer atypical antipsychotics. Further work should also include evaluation of adverse effects of pharmacological agents. Other research could include evaluation of combined pharmacotherapy and psychological treatment.
Self-harm (SH; intentional self-poisoning or self-injury regardless of degree of suicidal intent or other types of motivation) is a growing problem in most countries, often repeated, and associated with suicide. Evidence assessing the effectiveness of pharmacological agents and/or natural products in the treatment of SH is lacking, especially when compared with the evidence for psychosocial interventions. This review therefore updates a previous Cochrane Review (last published in 2015) on the role of pharmacological interventions for SH in adults.
To assess the effects of pharmacological agents or natural products for SH compared to comparison types of treatment (e.g. placebo or alternative pharmacological treatment) for adults (aged 18 years or older) who engage in SH.
We searched the Cochrane Common Mental Disorders Specialised Register, the Cochrane Library (Central Register of Controlled Trials [CENTRAL] and Cochrane Database of Systematic Reviews [CDSR]), together with MEDLINE. Ovid Embase and PsycINFO (to 4 July 2020).
We included all randomised controlled trials (RCTs) comparing pharmacological agents or natural products with placebo/alternative pharmacological treatment in individuals with a recent (within six months of trial entry) episode of SH resulting in presentation to hospital or clinical services. The primary outcome was the occurrence of a repeated episode of SH over a maximum follow-up period of two years. Secondary outcomes included treatment acceptability, treatment adherence, depression, hopelessness, general functioning, social functioning, suicidal ideation, and suicide.
We independently selected trials, extracted data, and appraised trial quality. For binary outcomes, we calculated odds ratios (ORs) and their 95% confidence internals (CIs). For continuous outcomes we calculated the mean difference (MD) or standardised mean difference (SMD) and 95% CI. The overall certainty of evidence for the primary outcome (i.e. repetition of SH at post-intervention) was appraised for each intervention using the GRADE approach.
We included data from seven trials with a total of 574 participants. Participants in these trials were predominately female (63.5%) with a mean age of 35.3 years (standard deviation (SD) 3.1 years). It is uncertain if newer generation antidepressants reduce repetition of SH compared to placebo (OR 0.59, 95% CI 0.29 to 1.19; N = 129; k = 2; very low-certainty evidence). There may be a lower rate of SH repetition for antipsychotics (21%) as compared to placebo (75%) (OR 0.09, 95% CI 0.02 to 0.50; N = 30; k = 1; low-certainty evidence). However, there was no evidence of a difference between antipsychotics compared to another comparator drug/dose for repetition of SH (OR 1.51, 95% CI 0.50 to 4.58; N = 53; k = 1; low-certainty evidence). There was also no evidence of a difference for mood stabilisers compared to placebo for repetition of SH (OR 0.99, 95% CI 0.33 to 2.95; N = 167; k = 1; very low-certainty evidence), or for natural products compared to placebo for repetition of SH (OR 1.33, 95% CI 0.38 to 4.62; N = 49; k = 1; lo- certainty) evidence.