When is sclerotherapy recommended for spider veins?

During sclerotherapy, a clinician injects a solution into selected small veins. The solution irritates the vein lining so the treated vessel closes and the body gradually clears it. It is mainly used for visible surface veins, while larger underlying veins may need a different assessment or treatment. New spider veins can appear later, and several appointments may be needed depending on the number, size, and distribution of veins.

Choose a qualified clinician who can inspect the veins and ask about aching, swelling, skin changes, previous clots, circulation problems, medicines, pregnancy, and allergies. Do not treat a new vein pattern without evaluation if one leg is swollen or painful. Discuss the injected solution, preparation, compression advice, activity after treatment, sun protection, and when the appearance should be reviewed. Follow instructions about medicines rather than changing them on your own.

Seek urgent care for sudden one-sided leg swelling, warmth, redness, significant pain, chest pain, or breathlessness. After treatment, contact the clinic about severe or increasing pain, marked swelling, skin breakdown, spreading redness, or an allergic reaction. A vein that becomes hard and tender can need review, especially if symptoms are worsening rather than settling.

Ask whether the visible veins are appropriate for sclerotherapy, whether deeper veins need checking, what alternatives exist, and what changes should prompt a follow-up visit.