This DNA test helps you discover your response to certain mental health medications, including antidepressants and antipsychotics. The test identifies common genetic variations in the genes encoding drug metabolising enzymes (e.g. Cytochrome P450 enzymes), which can result in changes to the activity of these enzymes. For example, for an intermediate or poor metaboliser, reduced metabolism results in increased plasma concentrations of the substrate medication. This can lead to an increased risk of side effects and toxicity from standard doses. Alternatively, a rapid or ultrarapid metaboliser, with overly efficient elimination of the substrate medication results in reduced plasma concentrations. This can lead to less medication being available for clinical effect, and potentially therapeutic failure.