Which symptom is NOT commonly associated with a hypersensitivity reaction to penicillin?

A headache is not commonly considered a symptom associated with a hypersensitivity reaction to penicillin. Hypersensitivity reactions to penicillin typically manifest as skin rashes, respiratory symptoms like shortness of breath, and wheezing. These symptoms arise due to an immune response to the drug, which can involve the skin or respiratory tract primarily.

Rashes are particularly common and can vary from mild to severe. Similarly, respiratory symptoms occur due to bronchoconstriction or airway inflammation triggered by the immune system's reaction to the penicillin. These symptoms are part of the body's immediate or delayed hypersensitivity responses.

In contrast, headaches do not have a direct link with the immunological pathways involved in penicillin hypersensitivity. While they can occur for various reasons, they are not specifically tied to allergic reactions in this context. Thus, identifying headaches as a symptom in this context is inaccurate.