Pigmentation and Matting After Sclerotherapy: Why They Happen and How They Fade
Brown staining after sclerotherapy is iron pigment left in the skin by blood trapped in the treated vein. Matting is a blush of very fine red vessels near the treated area. Both are common and usually temporary: most staining fades within three to six months and most matting within a few months, though some staining lasts a year or more.
A brown line two weeks after treatment often worries patients. Usually nothing has gone wrong. For the treatment itself, see how sclerotherapy works; for the procedure at the clinic, see sclerotherapy in Dubai.
Brown Staining: Iron Left Behind in the Skin
Post-sclerotherapy pigmentation, also called haemosiderin staining, is a brown line tracing the treated vein or brown spots at the injection sites. As the sclerosant damages the vein, blood can be trapped inside it or leak into the surrounding tissue. When those red cells break down, their iron is left behind as a pigment called haemosiderin, which shows through the skin.
How common is it? The authors of a multicentre trial in the Journal of Vascular Surgery cite nearly 30 per cent of patients. A systematic review of 27 studies found rates rising with the strength of the sclerosant: for spider and reticular veins, 2 to 25 per cent with 0.25 per cent polidocanol and 12.5 to 68 per cent with 0.5 per cent. The wide ranges reflect differences in how studies measured it.
This is not the same as the brown skin around the ankle in long-standing venous disease, which has a different cause and course.
Matting: Fine New Vessels Near the Treated Vein
Telangiectatic matting is a fine network of red vessels, each under 0.2 mm wide, that can appear days or weeks after treatment. In a review of 2,120 patients treated in one practice, 16 per cent developed it. Why it happens is not fully understood.
Matting is a reaction around a treated area. It is a different question from spider veins coming back months or years later in new places, which is covered in why spider veins return after treatment.
Who Is More Prone to Each
Staining is more likely with:
a stronger concentration of sclerosant;
veins lying just under the skin, compared with deeper trunk veins;
blood trapped in the treated vein;
certain antibiotics taken around the time of treatment, which Cleveland Clinic notes can stain the skin.
Matting was more common, in the same 2,120-patient review, in people who were overweight, who were taking hormones during treatment, who had a family history of spider veins, or whose spider veins had been present for longer. Long hours on your feet, common in Dubai's retail and hospitality work, did not raise the risk. A Cochrane review of 35 randomised trials, summarised in the 2023 Society for Vascular Surgery guideline, found that foam probably causes more matting than liquid, and that sodium tetradecyl sulphate caused more staining and matting than other agents. The same guideline recommends liquid or foam sclerotherapy for symptomatic spider and reticular veins, and Dr. Sohrabi treats them with sclerotherapy in line with that guidance. Foam is still used for larger veins, as explained in sclerotherapy for varicose veins.
Does skin type matter? Darker skin stains more often. A recent tissue study of 20 skin biopsies found that the stain is not only iron: in some patients the skin also lays down extra melanin in response to the inflammation, and a dermatology review notes that this kind of pigment change affects darker skin more often and more severely.
What Lowers the Risk
No technique removes the risk entirely. Several steps reduce it:
The lowest strength that closes the vein. Staining rises with concentration, so the solution is matched to the size of each vessel.
Releasing trapped blood. In a randomised trial of 101 patients, draining trapped blood one to three weeks after treatment reduced staining in veins of 1 mm or less. In veins up to 3 mm it did not reduce staining, but it eased pain and inflammation faster.
Compression. In a trial of 100 women, three weeks of stockings improved how well the treated vessels cleared; staining and matting were uncommon in both groups and did not differ.
Telling the clinician about antibiotics taken in the 7 to 10 days either side of treatment.
Sun protection. Dubai sun is strong for most of the year, and Dr. Sohrabi asks patients to protect treated skin from the sun for two weeks.
How Each Fades, and What Helps If It Lingers
Time does most of the work. According to Cleveland Clinic, brown lines or spots usually go within three to six months, and new tiny vessels fade within a few months and probably will not need more treatment. In the systematic review, staining lasted beyond six months in up to 7.5 per cent of reported cases, and beyond a year in 8 to 17.5 per cent after foam to larger trunk veins.
For staining that persists, releasing any remaining trapped blood helps early on. Staining that does not fade can be treated with laser, which the same tissue study describes as the main treatment option.
Matting that does not fade may need the vein feeding it treated. A duplex ultrasound scan can show whether a leaking vein beneath is keeping the fine vessels filled.
Dr. Soroush Sohrabi is a UK-trained Consultant Vascular and Endovascular Surgeon (FRCS, CCT) practising in Dubai, with a Cleveland Clinic Advanced Endovascular Fellowship and 77 peer-reviewed publications.
Choosing a Surgeon Who Plans for Side Effects
Ask before treatment what happens if staining or matting appears, and who will see you about it. Dr. Sohrabi holds the FRCS in Vascular Surgery and a CCT, performs and interprets his own duplex scans, treats spider, reticular and varicose veins with sclerotherapy and closes leaking main veins by ablation, so a feeding vein behind lingering matting can be found and treated. Book a consultation to talk through your veins and your skin.
About the Author
Dr. Soroush Sohrabi MD, PhD, FRCS, CCT (UK), PGCert, MCPhleb is a Consultant Vascular and Endovascular Surgeon practising in Dubai. He trained in the United Kingdom and holds a Fellowship of the Royal College of Surgeons (FRCS) in Vascular Surgery and a Certificate of Completion of Training (CCT). He has published 77 peer-reviewed papers with over 1,183 academic citations and is a member of the European Society for Vascular Surgery (ESVS) and the Vascular Society of Great Britain and Ireland (VSGBI). He is licensed by the UK General Medical Council (GMC No. 5207627) and the Dubai Health Authority (DHA No. 48905551).
Medically reviewed by Dr. Soroush Sohrabi MD, PhD, FRCS, CCT, Consultant Vascular and Endovascular Surgeon, October 2026.
References
Cleveland Clinic. Sclerotherapy: Treatment and Recovery. https://my.clevelandclinic.org/health/treatments/6763-sclerotherapy
Gloviczki P, Lawrence PF, Wasan SM, et al. The 2023 Society for Vascular Surgery, American Venous Forum, and American Vein and Lymphatic Society clinical practice guidelines for the management of varicose veins of the lower extremities. Part II. Journal of Vascular Surgery: Venous and Lymphatic Disorders. 2024;12(1):101670. https://doi.org/10.1016/j.jvsv.2023.08.011
Scultetus AH, Villavicencio JL, Kao TC, et al. Microthrombectomy reduces postsclerotherapy pigmentation: multicenter randomized trial. Journal of Vascular Surgery. 2003;38(5):896-903. https://doi.org/10.1016/s0741-5214(03)00920-0
Bossart S, Daneluzzi C, Cazzaniga S, et al. Skin hyperpigmentation after sclerotherapy with polidocanol: a systematic review. Journal of the European Academy of Dermatology and Venereology. 2023;37(2):274-283. https://doi.org/10.1111/jdv.18639
Davis LT, Duffy DM. Determination of incidence and risk factors for postsclerotherapy telangiectatic matting of the lower extremity: a retrospective analysis. Journal of Dermatologic Surgery and Oncology. 1990;16(4):327-330. https://doi.org/10.1111/j.1524-4725.1990.tb00043.x
Kern P, Ramelet AA, Wütschert R, et al. Compression after sclerotherapy for telangiectasias and reticular leg veins: a randomized controlled study. Journal of Vascular Surgery. 2007;45(6):1212-1216. https://doi.org/10.1016/j.jvs.2007.02.039
Bossart S, Ramelet AA, Seyed Jafari SM, et al. Revealing the origin of postsclerotherapy hyperpigmentation: identification of melanin and hemosiderin as causative pigments in a histopathological study. Phlebology. 2026;41(3):217-223. https://doi.org/10.1177/02683555251357095
Davis EC, Callender VD. Postinflammatory hyperpigmentation: a review of the epidemiology, clinical features, and treatment options in skin of color. Journal of Clinical and Aesthetic Dermatology. 2010;3(7):20-31. PMID 20725554 (PMC2921758).
