The influence of anxiety and locus of control on adolescents' response to naproxen sodium for mild to moderate pain

This study assessed the influence of internal health locus of control (IHLC) and anxiety on the adolescent's response to the treatment of mild and moderate pain. Fifty-four adolescents (ages 16-22 years) front two adolescent clinics presenting with mild to moderate pain caused by dysmenorrhea, muscle sprain or strain, headache, or backache were studied. Following a physical examination and a pretest assessment of pain, IHLC, and the Spielberger State-Trait Anxiety Inventory, subjects were randomly assigned in a double-blind fashion to groups receiving placebo (n = 16), 100 mg of naproxen sodium (n = 19), or 200 mg naproxen sodium (n = 19) and assessed at 1, 2, 3, and 4 hours Based on a repeated-measure analysis of covariance test, there were no differences between groups in the pretest measurements. All treatment groups had a decrease in pain over the 4 hours (p < 0.0001). Patients from one institution had more pain reduction than at the other (p < 0.0001), and females had more pain reduction than males (p < 0.034). Subjects receiving 200 mg of naproxen sodium had more pain relief (p < 0.034) than subjects taking placebo at hour 2. Baseline anxiety was positively associated with pain after receiving placebo, but inversely associated with pain after taking naproxen sodium. The IHLC appeared to have a positive effect on the response to naproxen sodium, but no effect on the response to placebo.