- Visit 2 (week 0): Baseline visit (60-90 min). Participants complete the VAS pain scale, and if their pain is above a designated level and no changes in clinical status are reported, they complete a battery of questionnaires and undergo fMRI procedures (anatomical and functional scans). Participants will then be randomized to one of three groups: active treatment, or placebo, or no-treatment groups; this is done in a partially blind fashion (explained below), with medication dispensed in sufficient quantities until the next visit. The placebo group will receive two placebo capsule bid, and the standard of care group will receive one naproxen capsule (500mg) and one esomeprazole capsule (20 mg) bid for the treatment period. The active and placebo treatment groups are double-blinded, meaning that neither the participant nor the researchers will know which treatment participants are receiving (in part through the use of identical re-encapsulation of study agents). The no-treatment group allocation is not blind, as both participants and study staff will be aware that these participants are not receiving study agent. The no treatment group and all participants assigned to a treatment group will continue to receive rescue medication (n=20).