Adverse effects and perceived benefits of medications in children with chronic noncancer pain.

Background: There has been limited research in assessing the risk-benefit profile of pharmacological interventions for pediatric chronic pain. Aims: This quality-improvement analysis evaluated the incidence of adverse effects within the first month of initiating pharmacologic therapy in children and adolescents with chronic non-cancer pain receiving pharmacological treatment. In addition, we assessed perceived benefits of pharmacologic interventions during the same period. Methods: We included pediatric patients with chronic primary or secondary pain enrolled in tertiary care interdisciplinary pain program. The primary endpoint was the proportion of patients reporting adverse effects within four weeks of starting a new medication (antiepileptics, antidepressants, nonsteroidal anti-inflammatory drugs, Tramadol or other drugs). Patients were provided with a tabulated adverse effects (5% or higher) for each medication they were receiving. We quantified the incidence of adverse effects, but severity of the adverse effects, causality or pharmacological interactions were not assessed. The secondary outcome was the proportion of patients reporting benefit as a dichotomous variable (Yes or No) in pain, sleep, physical function and mood. Each domain was treated as an independent, non-composite variable without graded scales. Results: 142 patients aged 7-17 with chronic, predominantly female (90%) received 291 prescriptions (mean 2.0 per patient). Adverse effects occurred in 115/142 patients (81%), totaling 572 events (mean 2.0 per patient). Gastrointestinal (62%) and attention-related (61%) were the most common reported adverse effects. Adverse effects increased with more concomitant medications (72% on one drug, 81% on two drugs, 95% on three or more). Perceived benefits were reported by 109 patients (77%), including analgesic benefit (64%), sleep benefits (49%), physical function (27%), and mood (22%). The mean number of benefited domains per patient increased with polypharmacy. However, the number of perceived benefits per prescription decreased with the number of medications prescribed. Conclusions: Adverse effects are common in the first four weeks of treatment, particularly with polypharmacy, alongside patient-perceived benefits in a real-world setting. These results are descriptive and do not establish causality, drug-specific efficacy, or interactions, but highlight the need for safety monitoring and engaged decision-making.