Which assessment indicates an immediate need to discontinue an antibiotic?

Discontinuing an antibiotic is critical when a patient exhibits a skin rash, particularly if the rash appears suddenly and is accompanied by other signs of an allergic reaction. Skin rashes can be indicative of hypersensitivity reactions, which can escalate to more severe conditions such as anaphylaxis or toxic epidermal necrolysis. Early identification and cessation of the offending antibiotic can prevent possible serious complications.

In contrast, increased heart rate, fatigue, and fever are symptoms that may require further assessment but do not necessarily warrant an immediate stop to antibiotic treatment without considering the context. For instance, fever may indicate infection, while fatigue could result from the infection itself or other factors and doesn't specifically link to an immediate reaction to antibiotics. Thus, a skin rash stands out as a clear indicator for the need to discontinue the medication quickly.