What is the recommended dosing guide for sclerotherapy (using polidocanol) in the treatment of varicose veins?

Recommended Dosing Guide for Polidocanol Sclerotherapy in Varicose Veins

For varicose vein sclerotherapy, use polidocanol 0.5% for spider veins (≤1 mm) and 1% for reticular veins (1-3 mm), with 0.1-0.3 mL per injection site and maximum 10 mL per session. 1

Dosing Based on Vein Size

The FDA-approved dosing for polidocanol (Asclera) is specifically tailored to vein diameter:

• Spider veins (≤1 mm diameter): Use 0.5% polidocanol solution
• Reticular veins (1-3 mm diameter): Use 1% polidocanol solution
• Injection volume: 0.1-0.3 mL per injection site
• Maximum volume per session: 10 mL
• Administration: Use a fine needle (26- or 30-gauge) inserted tangentially into the vein with gentle pressure 1

Note: Polidocanol has not been studied in varicose veins larger than 3 mm in diameter.

Post-Injection Compression Protocol

Proper post-injection compression is critical for efficacy and safety:

• Spider veins: Maintain compression for 2-3 days
• Reticular veins: Maintain compression for 5-7 days
• Extensive varicosities: Longer compression with higher compression class stockings/bandages
• Immediate post-treatment: Patient should walk for 15-20 minutes after treatment 1

Treatment Schedule

• For extensive varicosities requiring more than 10 mL, separate treatments by 1-2 weeks
• Small intravaricose thrombi may be removed by microthrombectomy 1

Safety Considerations

Contraindications

• Known allergy to polidocanol
• Acute thromboembolic diseases 1

Important Precautions

• Risk of anaphylaxis: Be prepared to treat severe allergic reactions, which are more frequent with larger volumes (>3 mL)
• Risk of tissue necrosis: Ensure proper intravenous placement and use smallest effective volume
• Risk of DVT: Post-treatment compression is necessary to reduce deep vein thrombosis risk 1
• Monitoring: Keep patient under observation after injection to detect any anaphylactic or allergic reactions 1

Efficacy Evidence

Sclerotherapy with polidocanol has demonstrated effectiveness compared to placebo:

• Improved cosmetic appearance
• Decreased rates of residual varicose veins
• Improved quality of life
• Improved venous clinical severity scores 2

Concentration Considerations

While the FDA-approved concentrations are 0.5% and 1%, clinical experience suggests:

• Higher concentrations (3%) of polidocanol may be more effective for larger veins with a 95% success rate compared to lower concentrations 3
• Low concentrations (0.3-0.6%) can be effective for larger varicose veins if adequate volume is injected 4

Administration Technique

• Insert needle tangentially into the vein
• Inject solution slowly while needle remains in the vein
• Apply only gentle pressure during injection to prevent vein rupture
• Cover injection site after needle removal
• Apply compression stocking or bandage immediately after treatment 1

Common Pitfalls to Avoid

1. Exceeding maximum volume: Never exceed 10 mL per session
2. Inadequate compression: Failure to apply proper post-treatment compression increases complication risk
3. Intra-arterial injection: Can lead to tissue ischemia and necrosis
4. Treating large veins: Polidocanol is not FDA-approved for veins >3 mm
5. Ignoring contraindications: Do not use in patients with known polidocanol allergy or acute thromboembolic disease

By following these dosing guidelines, sclerotherapy with polidocanol can be an effective treatment for varicose veins with a low incidence of complications when performed properly 5.