MRCP2-4667

A 29-year-old woman presents to rheumatology with a one-year history of painful hands that change colour in cold weather. She reports a white, blue, and then red discoloration followed by symptom resolution. She denies any other symptoms or medical history. On examination, her hands are blue-white and cool to touch, but there is no ulceration or scarring. Blood tests are negative for autoimmune and infectious causes. What is the recommended initial pharmacological management for this likely diagnosis?