What is sclerotherapy?
Sclerotherapy is a procedure in which a sclerosing solution is injected directly into the vein, causing the vein to collapse and seal shut, redirecting blood flow to healthier veins. After injection, the treated veins gradually close off over several weeks. Within a few months, the body removes the dead vein tissue, leaving only minimal scarring.
The term “sclerotherapy” comes from the Greek words “skleros” (hard) and “therapeia” (treatment).
Which stages of venous insufficiency can be treated with sclerotherapy?
Sclerotherapy is recommended for treating superficial venous insufficiency at grade 1, particularly reticular veins (with diameters ranging from 1–3 mm). This is the ideal size range for a needle to reach the vein lumen through the skin. For smaller vessels under 1 mm—especially those under 0.5 mm—long-pulsed laser is commonly used to induce sclerosis by acting externally on the skin surface (primarily via the photocoagulation effect of the laser).

Steps of Sclerotherapy Treatment
Advantages of Sclerotherapy
Sclerotherapy is a minimally invasive technique that offers many advantages over traditional vein stripping surgery. It delivers a range of clinical benefits, such as:
- Minimally invasive: No surgery required
- Quick procedure: Takes only 15–30 minutes
- High efficacy: Success rate up to 90%
- Fast recovery: Patients can walk immediately after the procedure
- Low risk of complications: Safer than traditional vein stripping surgery
- Effective for reticular veins
Possible complications of sclerotherapy
Dr. Le Kim Cao outlines several possible side effects or complications that may occur after sclerotherapy, including:
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- Injection-site pain: A mild to moderate discomfort may occur along the treated vein. However, this is typically temporary and resolves quickly.
- Temporary hyperpigmentation: Around 15% of patients report mild skin discoloration (light brown spots) after treatment. This usually fades within 4 to 12 months, although in some cases, it may persist for years.
- Blisters or skin ulceration: If not administered by an experienced vascular surgeon, the sclerosant may leak into surrounding tissue, potentially causing blistering or ulcer formation.
- Refill phenomenon: Seen in 20–40% of cases after basic sclerotherapy, where treated veins refill and reappear.
- Deep vein thrombosis (DVT): The formation of blood clots in deep veins, which may lead to pulmonary embolism (PE). Sclerotherapy is contraindicated in patients with DVT due to the risk of severe complications, including fatal outcomes.
Post-Sclerotherapy Care Instructions
Precautions after sclerotherapy:
- Avoid direct sun exposure for 2–4 weeks.
- Avoid heavy physical activity and emotional stress within 24–48 hours.
- Drink plenty of water to reduce bruising and swelling.
- Avoid hot baths or soaking in hot water.
- Contact your doctor if you experience any unusual side effects.
Patients can stand and walk immediately after the procedure. Light walking and movement help prevent blood clot formation.
Wearing compression stockings or using compression therapy—for about two weeks—is recommended to increase venous pressure and support blood flow. Do not shave the treated area or apply any creams until the skin has fully healed.
Most patients return to normal daily activities on the same day without requiring rest. However, it is recommended to avoid strenuous exercise for at least one week after the procedure.
In addition, the treated area should not be exposed to direct sunlight for at least two weeks. It is best to use sunscreen with SPF 30+ to protect the area. Sun exposure may lead to skin discoloration, especially in individuals with darker skin tones.

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