A client is about to start taking an NSAID called celecoxib to treat osteoarthritis symptoms. The nurse should instruct the client to watch for and report which of the following possible indications of a serious reaction to the drug?

Choice A rationale Dry mouth is not a recognized serious adverse reaction associated with the use of celecoxib, which is a selective COX-2 inhibitor. This medication focuses on inhibiting the enzymes responsible for inflammation and pain. Dry mouth is more frequently associated with anticholinergic medications or certain antidepressants. While it can be uncomfortable, it does not represent a life-threatening systemic reaction requiring immediate provider notification. Choice B rationale Bone pain is usually a symptom of the underlying osteoarthritis rather than a side effect of celecoxib therapy itself. Celecoxib is intended to reduce the pain associated with musculoskeletal conditions by decreasing prostaglandin synthesis. If a patient experiences new or worsening bone pain, it may indicate disease progression or a different pathology, but it is not a hallmark warning sign of a serious drug reaction. Choice C rationale Polyuria, or excessive urination, is not a standard side effect or a warning sign of a serious adverse reaction to celecoxib. While NSAIDs can impact renal function by reducing blood flow to the kidneys through prostaglandin inhibition, this typically manifests as fluid retention, peripheral edema, or decreased urine output rather than increased frequency. Therefore, polyuria would not be the primary serious reaction to report. Choice D rationale Black tarry stools, or melena, indicate upper gastrointestinal bleeding which is a serious potential complication of NSAID therapy, including selective COX-2 inhibitors like celecoxib. Although celecoxib is designed to be easier on the stomach than non-selective NSAIDs, it still carries a black box warning for gastrointestinal risks. Bleeding occurs when the drug interferes with the protective mucosal lining, leading to ulceration and hemorrhage.