This case report describes a 42-year-old man who developed radiation-induced alopecia after an endovascular embolization procedure for a cerebral arteriovenous fistula. The alopecia appeared as a well-defined patch of hair loss on the right scalp, confirmed by biopsy showing lymphocytic infiltration and increased catagen and telogen follicles. The patient was treated with intramuscular corticosteroid injections and topical 5% minoxidil, leading to complete hair regrowth after three months. Radiation-induced alopecia, though rare and typically self-limiting, requires early diagnosis. This case highlights a novel therapeutic approach combining corticosteroids and minoxidil for faster recovery.