Which of the following is a possible adverse effect of Benzylpenicillin?

Benzylpenicillin is a type of penicillin antibiotic that can, in some cases, lead to hypersensitivity reactions. Urticaria, commonly known as hives, and angio-oedema are both potential manifestations of such allergic responses. Urticaria presents as raised, itchy welts on the skin, while angio-oedema involves swelling of the deeper layers of the skin, often around the eyes and lips, and may also affect the throat. These reactions can be serious and may require immediate medical attention.

While nausea and vomiting, diarrhea, and increased appetite can occur with other medications, they are not the typical adverse effects specifically associated with Benzylpenicillin. Nausea and diarrhea may arise from gastrointestinal irritation but are less specific to this antibiotic compared to the allergic manifestations. Increased appetite is not a recognized side effect of Benzylpenicillin. Therefore, urticaria and angio-oedema represent the most significant adverse effects of this antibiotic, highlighting the importance of monitoring for allergic reactions during treatment.