Sclerotherapy is a procedure where a sclerosant is injected directly into spider veins. The most common sclerosant used in the US is polidocanol
This procedure is performed by vascular surgeons, dermatologists, and plastic surgeons
The vessels immediately disappear after injection but then eventually become dark red/brown until they heal. Eventually, they permanently disappear
Although the results are permanent, new vessels can form if there is venous insufficiency in the deeper leg veins. Your doctor will ask you questions about leg symptoms, such as pain, to evaluate for deep venous disease
Side effects include blood clots (rare) and accidental injection of the surrounding tissue
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