If a patient taking Keflex for pneumonia experiences which symptom, they should seek immediate medical attention?

The correct choice is easy bruising, which could indicate a serious side effect or an adverse reaction related to the use of Keflex (cephalexin) or other factors. Easy bruising may be a sign of a bleeding disorder or a potential decrease in platelet count, which can happen as a reaction to medication or an underlying condition that warrants prompt evaluation by a healthcare provider. This symptom requires immediate medical attention to determine the cause and to initiate appropriate interventions.

Vaginal itching, joint pain, and nausea may also be concerning but are generally not considered emergencies that require immediate medical attention. Vaginal itching could be a sign of a yeast infection, which, while uncomfortable, usually does not pose an immediate risk. Joint pain can arise from various causes, including medication side effects or pre-existing conditions, but is not typically urgent unless accompanied by other severe symptoms. Nausea might indicate gastrointestinal side effects or intolerance to the medication but is not usually life-threatening without the presence of other alarming symptoms.