As mentioned previously, SSRIs are associated with various dose-dependent side effects, including nausea, diarrhoea, dizziness, headaches, insomnia, sedation, anxiety, sexual dysfunction, and decreased libido [1274, 1275]. As the dose required for a clinically significant improvement in OCD symptoms is typically higher than is required in the treatment of depressive disorders, the potential for unwanted side effects is substantially increased [1276, 1277]. As such, several studies have examined alternative therapies in the treatment of single disorder OCD.
In systematic reviews of complementary and alternative approaches, there is some evidence that health-based games [1278], art therapy, sports therapy, recreational therapy [1279], mindfulness meditation, electro-acupuncture, yoga, nutrient glycine, borage, and milk thistle may have a positive impact on OCD symptoms [1280]. However, it is important to note that a number of these studies used methodologically weak designs, and none examined use of these therapies among people with co-occurring OCD and AOD use.
Neurofeedback
Neurofeedback involves providing auditory or visual feedback for suppressing or producing certain brain waves, enabling people to self-regulate their brain activity. One systematic review and meta-analysis suggests that neurofeedback effectively reduces OCD symptoms among those with single disorder OCD compared to control conditions [1281]. While promising, it should be noted that included studies varied in terms of their design and validity, and drawing conclusions is therefore difficult. Further, the effects of neurofeedback are yet to be evaluated among people with co-occurring OCD and AOD use.
Deep brain stimulation
Deep brain stimulation is a neurosurgical procedure which involves embedding microelectrodes in brain areas involved in single disorder OCD treatment, and using an electric current to directly stimulate the embedded microelectrodes and associated brain regions [1282]. Several reviews provide evidence that deep brain stimulation effectively reduces OCD symptoms by 20-46% [1282–1284] compared to control conditions. Deep brain stimulation may be particularly useful for people with treatment resistant OCD [1282]. However, one-third of people who receive deep brain stimulation experience serious adverse side effects such as brain haemorrhage and infection [1283], and to date there is no evidence on the efficacy of deep brain stimulation among people with co-occurring OCD and AOD use.