Sclerotherapy

Short answer: Sclerotherapy treats unwanted veins by injecting a solution (a sclerosant) that damages the vein's inner lining, the endothelium. The vein then becomes inflamed, scars and closes, and over weeks to months the body clears it and it fades.

It's used for spider veins (telangiectasias), small reticular veins and some varicose veins. For larger varicose veins, the sclerosant is often whipped into a foam and injected under ultrasound guidance, a technique NICE has assessed in its guidance. The sclerosants in widest use are detergents such as polidocanol and sodium tetradecyl sulfate, which break down the cell membranes of the lining. Hypertonic saline, a concentrated salt solution, works by drawing water out of the cells. It's one option, but not the usual one, and ordinary saline wouldn't close a vein. Several sessions may be needed. Clinical sources list common effects such as pain at the injection site, bruising, temporary lumps, brown staining of the skin and new tiny red veins ('matting'). They list rare complications including skin ulcers, allergic reactions, and clots in deeper veins. This case is general information, not medical advice. The footage shows a needle injecting into small purple veins on a leg.

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