Sclerosant
Sodium tetradecyl sulfate
Brand names: Fibrovein, Sotradecol
Sodium tetradecyl sulfate is a sclerosant injected to treat varicose veins and other unwanted veins by sclerotherapy.
Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.
Adult dose
Dose: Varicose vein sclerotherapy, adults — normal volume injected intravenously at suitable sites per session, by strength: Fibrovein 3% = 0.5 to 2.0 mL as liquid, or 0.5 to 2.0 mL as foam; Fibrovein 1% = 0.1 to 1.0 mL as liquid, or 0.5 to 2.0 mL as foam; Fibrovein 0.5% and 0.2% = 0.1 to 1.0 mL as liquid (foam not applicable). Strength is chosen by vessel: 'Spider veins should only be treated with the 0.2%, reticular veins with 0.5%, the 1% solution will be found most useful for small to medium varicosities and the 3% solution for larger varicosities.'
Route: Intravenous use only — 'The sclerosant should be administered intravenously in small aliquots at multiple sites along the vein to be treated either as a liquid or as a sclerosant/air mixture (foam), for the treatment of larger veins with the 1% and 3% solutions.' Indication: sclerotherapy of varicose veins.
Frequency: Per treatment session. 'As the volume to be injected is limited per session, repeated sessions are usually needed (2 to 4 on average).'
Max: Maximum total volume to be injected per session (SPC §4.2 table): Fibrovein 3% — 4 mL as liquid, 16 mL as foam; Fibrovein 1% — 10 mL as liquid, 16 mL as foam; Fibrovein 0.5% and 0.2% — 10 mL as liquid (foam not applicable). For foam, 'volume is the sum of the liquid and air components'. The US label states 'the maximum single treatment should not exceed 10 mL'.
Objective of dosing: 'The objective is to achieve optimal destruction of the vessel wall with the minimum concentration of sclerosant necessary for a clinical result. If the concentration is too high necrosis or other adverse sequelae may occur.' §4.8 reinforces: 'It is important to use the lowest strength that will sclerose the vein as many of the common side effects are caused by using a concentration that is too high.' TEST DOSE: 'Where special caution is indicated it is recommended that a test dose of 0.25 to 0.5 ml Fibrovein should be given followed by observation of the patient for several hours before administration of a second or larger dose'; and 'To prevent a possible allergic reaction, it is recommended that a small test dose of Fibrovein should be given at the beginning of each session.' SIZING: 'The size of non-visible varicose veins should be measured under ultrasound.' FOAM: only the 3% and 1% solutions may be converted to foam; 'The foam must be prepared just before use and administered by a physician appropriately trained in the correct generation and administration of foam. It should ideally be administered under ultra sound guidance' (Tessari method described in §6.6). Truncular varicosities: 'there should be a minimal distance of 8 to 10 cm between the site of foam injection and the saphenofemoral junction.' Elderly: 'No specific dose recommendations apply.' Handling: strict aseptic technique; single-use parenteral product — once opened use immediately and discard any unused portion; do not use if particulate matter is present. The US label adds that heparin 'should not be included in the same syringe as sodium tetradecyl sulfate injection, since the two are incompatible.' PAEDIATRICS: §4.2 'The safety and efficacy of Fibrovein in children and adolescents have not been established. No data are available' (US label: 'Safety and effectiveness in pediatric patients have not been established') — hence paedDose is null.
Dose adjustments
Renal
Not stated — the fetched UK SPC §4.2 special-population text covers only the elderly and the paediatric population, and gives no renal dosing statement; the fetched US sections give none either.
Hepatic
Not stated — no hepatic-impairment dosing statement appears in the fetched sections of either label.
Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.
Contraindications
- Hypersensitivity to the active substance or any of the excipients, and allergic conditions (§4.3)
- Unable to walk due to any cause, bedridden
- High risk of thrombosis, e.g. a congenital predisposition to blood clots or multiple risk factors such as hormonal contraception or hormone replacement therapy, significant obesity, smoking or extended periods of immobility
- Recent acute superficial thrombophlebitis, deep vein thrombosis or pulmonary embolism
- Recent surgery
- Varicosities caused by pelvic or abdominal tumours unless the tumour has been removed
- Uncontrolled systemic disease such as diabetes mellitus, toxic hyperthyroidism, tuberculosis, asthma, neoplasm, sepsis, blood dyscrasias and acute respiratory or skin diseases
- Evolutive cancer
- Significant valvular incompetence of the deep veins
- Occlusive arterial disease
- Huge superficial veins with wide open communications to deeper veins
- Phlebitis migrans
- Acute cellulitis
- Acute infections
- When the sclerosant has been converted to foam: known symptomatic patent foramen ovale (PFO)
Side effects
- Pain on injection, urticaria, superficial thrombophlebitis and temporary skin pigmentation after treatment — 'The most commonly reported side effects' (§4.8); very rarely a permanent discoloration may remain along the path of the sclerosed vein segment
- Superficial thrombophlebitis / phlebitis — common with liquid, very common with foam
- Matting (growth of very fine spider veins in the treated area) — uncommon with liquid, common with foam
- Ulceration following extravasation of the drug; nerve damage after extravasation (very rare)
- Deep vein thrombosis (mostly muscular and distal) — very rare with liquid, uncommon with foam
- Migraine — very rare with liquid, uncommon with foam; headache, local sensitivity disturbances (paraesthesia); scotoma / scintillating scotoma — very rare with liquid, uncommon with foam
- Vaso-vagal reactions (fainting, confusion, dizziness, loss of consciousness) — very rare with liquid, rare with foam
- Weakness (hemiparesis, hemiplegia), transient ischaemic attack, palpitations, stroke — very rare
- Coughing, shortness of breath, sensation of pressure/tightness in the chest — very rare with liquid, rare with foam
- Pulmonary embolism, vasculitis, circulatory collapse — very rare
- Distal tissue necrosis following intra-arterial injection, which may lead to gangrene — very rare; 'Most cases have involved the posterior tibial artery above the medial malleolus. Arterial spasm can occur despite intravenous injection'
- Systemic allergic reactions e.g. anaphylactic shock, asthma, generalised hives — very rare; 'The most serious side effects are anaphylactic shock and pulmonary embolism and deaths have been reported in patients receiving sodium tetradecyl sulfate' (US label: 'At least six deaths have been reported', four from anaphylactic shock)
Monitoring
- Operator and setting (§4.4): 'Fibrovein should only be administered by a healthcare professional experienced in venous anatomy and the diagnosis and treatment of conditions affecting the venous system and familiar with proper injection technique.
- Emergency resuscitation equipment should be immediately available.' Anaphylaxis must be anticipated and treatable.
- Observe the patient for several hours after a 0.25‑0.5 mL test dose where special caution is indicated.
- Before treatment, investigate the patient's thromboembolic risk factors and inform them of the risks of the technique
- sclerotherapy 'is notably not recommended in patients with a history of thromboembolic events' — if judged necessary, preventive anticoagulation can be initiated.
- PFO: in patients with a history of migraine with aura, serious cerebrovascular events or pulmonary hypertension, 'it is recommended to search for PFO before sclerotherapy'
- in asymptomatic but known PFO 'it is recommended to use smaller volumes and avoid Valsalva manoeuvre in the minutes after injection'.
- Use smaller volumes in patients with a history of migraine
- treat patients with previous TIA with care.
- Foam should ideally be administered under ultrasound guidance.
- Inspect visually for particulate matter before use.
Clinical monograph
How it works
As a detergent sclerosant it damages the venous endothelium, provoking inflammation and fibrosis that obliterate the treated vein.
Prescribing in practice
- Inadvertent extravasation or intra-arterial injection can cause tissue necrosis, and anaphylaxis and deep vein thrombosis are recognised risks, so it should be administered only by clinicians trained in sclerotherapy.
- A small test injection is advisable to identify hypersensitivity before fuller treatment.
- Compression and post-procedure mobilisation are used to reduce the risk of thrombotic complications.
Monitoring
Observe the injection site and patient for hypersensitivity, extravasation and signs of venous thromboembolism after treatment.
Counselling the patient
- Wear the compression bandaging or stockings as instructed after the procedure.
- Keep mobile and report calf pain, swelling, skin ulceration or breathlessness.
- Some bruising, pigmentation and discomfort at treated sites is expected.
Evidence & guidelines
Sodium tetradecyl sulfate is an established detergent sclerosant for varicose vein sclerotherapy.
Reference: NICE CG168/IPG440; SmPC; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).
Related
Curated clinical cross-links plus same-class fallbacks.
Calculators