Bladder dysfunction and behavioural disorders in children are commonly concomitant; hence, it is difficult to treat each in isolation. Pharmacotherapy is common treatment for behavioural disorders, and these medications may have intended or unintended positive or negative bladder sequelae. This review identifies the literature regarding the effects of behavioural pharmacotherapy on bladder functioning and possible bladder management strategies in children with concomitant behaviour and bladder disorders to enable clinicians to better manage both conditions. A PROSPERO registered PRISMA-guided review of three major databases was performed. After an initial scoping study revealed significant heterogeneity, a narrative approach was undertaken to discuss the results of all relevant cases relating to children being treated with pharmacotherapy for behaviour disorders and outcomes related to bladder function. Studies were screened to identify those that described effects of commonly prescribed medications in children with behavioural disorders such as stimulants, alpha 2 agonists, tricyclic antidepressants (TCA), serotonin and noradrenergic reuptake inhibitors (SNRI), selective serotonin reuptake inhibitors (SSRI) and antipsychotics, and the findings and implications were summarised. The review identified 46 studies relevant to behavioural pharmacotherapy and bladder function (stimulants (n = 9), alpha 2 agonists (n = 2), TCAs (n = 7), SNRIs (n = 8), SSRIs (n = 8) and antipsychotics (n = 6). Six studies focused specifically on bladder management in children with behavioural disorders with concurrent behavioural pharmacotherapy. This review identifies useful factors that may assist clinicians with predicting unintended bladder effects following initiation of behavioural pharmacotherapy to facilitate the best approach to the treatment of bladder dysfunction in children with behavioural disorders. With this evidence, we have provided a useful decision-making algorithm to aide clinicians in the management of these dual pathologies.