Lauromacrogol: sclerosing agent and topical local anaesthetic
Lauromacrogol (also known as polidocanol or Aethoxysklerol) is a non ionic surfactant with two clinically very different fields of use: as a sclerosant for varicose veins and haemorrhoids, and as a topical local anaesthetic for itch and minor skin lesions. Introduced in 1936, lauromacrogol is now an established part of phlebology and proctology.
In dermatology lauromacrogol is widely included in OTC creams and gels (e.g. Optiderm, in some countries Anaesthesin ointment), often combined with urea or other emollients.
Mechanism of action
Lauromacrogol acts via two different mechanisms:
- As a sclerosant: after injection into a vein, the drug destroys the endothelium of the vessel wall. The damaged endothelial cells trigger local inflammation leading to thrombus formation and subsequent fibrous transformation of the lumen. The vein is permanently obliterated
- As a local anaesthetic: when applied topically, lauromacrogol blocks sodium channels in peripheral nerve fibres and reduces the sensation of pain and itch
The sclerosing effect is dose dependent: higher concentrations are used in larger vessels, lower concentrations in fine spider veins. Foam sclerotherapy (foaming lauromacrogol with air or gas in a syringe) increases volume and contact area with the endothelium, particularly effective in truncal veins.
Indications
- Sclerotherapy of varicose veins: spider veins, reticular varices, truncal varices (great and small saphenous vein), tributary varices
- Haemorrhoid sclerotherapy: stage 1 and 2
- Telangiectasia at various sites
- Lymphangiomas and some vascular malformations: in specialised centres
- Gastrointestinal varices: endoscopic sclerotherapy as alternative to band ligation
- Topical: itch in dry skin, minor abrasions, mild sunburn, insect bites
Dosing and administration
Sclerotherapy: concentrations from 0.25 % to 3 % depending on vessel size. Spider veins 0.25 to 0.5 %, reticular varices 1 %, truncal varices 2 to 3 % as foam. Maximum single dose 2 mg per kg body weight per session.
Haemorrhoids: injection of 1 to 2 ml of a 1 % solution into the haemorrhoid or submucosal pedicle.
Topical use: apply cream or gel several times daily to itchy or irritated skin.
Sclerotherapy is performed in specialised practices or clinics. Before sclerotherapy of varicose veins, history, clinical examination, duplex ultrasound and exclusion of deep vein thrombosis are required. After sclerotherapy compression stockings or bandages are recommended for several days to weeks.
Adverse effects
Common after sclerotherapy: local irritation at the injection site, pain, hyperpigmentation of overlying skin, transient haematoma, superficial thrombophlebitis.
Uncommon: matting (formation of new fine spider veins in the treated area), skin necrosis after paravenous injection, allergic reactions, transient visual disturbance or migraine like symptoms with foam sclerotherapy.
Rare: deep vein thrombosis, pulmonary embolism, anaphylactic reactions, accidental arterial injection with tissue ischaemia and possible amputation, transient neurological symptoms with foam sclerotherapy (mainly with patent foramen ovale).
Topical common: mild local irritation, very rarely contact dermatitis.
Important points:
- Accidental arterial injection is the most serious complication
- For foam sclerotherapy medical observation for at least 30 minutes is sensible
- Hyperpigmentation can persist for months to years, particularly in darker skin types
- For dry itchy skin the topical form is well tolerated and easy to use
Interactions
- Hormonal contraceptives and HRT: increased thrombosis risk; cautious sclerotherapy with possible pause before treatment
- Anticoagulants: increased bleeding risk, careful indication
- Other sclerosants: do not combine in the same session
- Latex materials: caution with topical use combined with latex condoms or diaphragms
Special considerations
Pregnancy: sclerotherapy of varicose veins is not recommended in pregnancy. Topical use on small areas is acceptable.
Breastfeeding: topical use is possible; on the breast not directly before nursing.
Contraindications for sclerotherapy: acute deep vein thrombosis, severe peripheral arterial disease, local or systemic infection, severe allergy to lauromacrogol, immobilised patients, manifest hyperthyroidism, severe asthma.
Before sclerotherapy of varicose veins: duplex ultrasound to assess venous haemodynamics, exclusion of deep vein thrombosis, history for thromboembolism and allergy.
After sclerotherapy: compression treatment for several days to weeks, mobilisation, avoidance of heat and prolonged standing or sitting.
Patient communication: realistic information about multiple sessions, possible hyperpigmentation and the need for compression. In truncal varicose veins sclerotherapy is an alternative to surgery or thermal ablation, with individually variable success.
Related substances
- Aescin, plant derived agent in chronic venous insufficiency
- Rutoside, bioflavonoid in venous insufficiency
- Clopidogrel, platelet inhibitor in vascular medicine
- Dabigatran etexilate, DOAC in deep vein thrombosis
Frequently asked questions
How does sclerotherapy work?
Lauromacrogol is injected into the vein and destroys the endothelium. The damaged vein is converted by local inflammation into a fibrous cord and excluded from blood flow. Over weeks to months the treated vein disappears completely.
What is foam sclerotherapy?
Lauromacrogol solution is foamed in a syringe with air or a physiological gas, increasing volume four to five fold. The foam spreads better along the vessel wall and acts more strongly. Foam sclerotherapy is especially effective in truncal veins and larger varicose veins but carries a slightly higher complication risk.
How many sessions are needed?
For spider veins often 2 to 5 sessions a few weeks apart. For truncal varicose veins one session may be enough but follow up treatments are often required. Individual planning is based on duplex ultrasound and clinical assessment.
When is topical lauromacrogol useful?
For itchy dry skin, minor abrasions, mild sunburn and insect bites, topical lauromacrogol creams or gels can relieve symptoms. With chronic skin problems or unclear complaints medical clarification is appropriate.
Sources
- BfArM German Federal Institute for Drugs and Medical Devices
- EMA European Medicines Agency
- AWMF guidelines sclerotherapy and phlebology
- Gelbe Liste lauromacrogol monograph
Legal notice and disclaimer
The information on this page is provided for general information only and does not constitute medical advice, diagnosis or treatment recommendation. It does not replace advice from a qualified physician or pharmacist. Medicines should only be used on prescription or after dispensing by a pharmacist. All information is based on the product information available at the time of writing and on recognised scientific sources; the manufacturer's current product information always prevails. Sanoliste assumes no liability for completeness, timeliness or accuracy of the information presented. In a medical emergency call the European emergency number 112.