What could be the cause of a hard lump under the skin at the base of the penis, and what should be done about it?

A hard lump under the skin at the base of the penis may be caused by conditions such as folliculitis or sebaceous cysts.

1. Folliculitis is usually an infectious disease caused by blocked hair follicles, characterized by local redness, swelling, and pain. Treatment can involve applying medications such as fusidic acid cream or mupirocin ointment under the guidance of a doctor.

2. Sebaceous cysts are usually caused by the blockage of sebaceous glands, which leads to the accumulation of certain substances within the gland. As a result, round lumps appear on the skin, often accompanied by pain. These can be treated with medications such as penicillin or cephalosporins under the guidance of a doctor.

In daily life, it is important to maintain personal cleanliness and hygiene, follow a balanced diet, and avoid consuming spicy and irritating foods.