A nurse is caring for a client with a prescription for celecoxib (Celebrex). The nurse tells the client to report which of the following adverse drug reactions?

A. Diarrhea is a known side effect of celecoxib but not typically a sign of a serious reaction. B. Headache is a mild side effect that may occur with celecoxib use but is not a severe adverse reaction. C. Nausea is a common side effect of many medications, including celecoxib, but is not a critical issue unless severe. D. Chest pressure could indicate cardiovascular problems, which is a serious adverse effect of celecoxib and other COX-2 inhibitors. Clients should report this immediately, as it may indicate a risk for myocardial infarction or stroke.