1. Clinical Overview
Polidocanol is a non-ionic detergent sclerosing agent, chemically known as a hydroxypolyethoxydodecane. In the 30mg strength, it is primarily used as an injectable solution for the local treatment of uncomplicated varicose veins of the lower extremities (sclerotherapy). It acts by damaging the endothelium of the target vein, leading to thrombosis, fibrosis, and eventual obliteration of the vessel. It has local anesthetic properties due to its interaction with nerve cell membranes.
| Onset | Duration | Bioavailability |
|---|---|---|
| Endothelial damage begins within seconds of injection. Clinical sclerosis and vein occlusion typically occur over days to weeks. | The sclerosing effect is permanent for the treated vein segment. The drug is locally metabolized and eliminated. | Not applicable (N/A) for injectable local administration. Systemic absorption is minimal when administered correctly. |
2. Mechanism of Action
Polidocanol is a detergent sclerosant. Upon intravenous injection, it disrupts the lipid bilayer of endothelial cell membranes, causing immediate endothelial damage and denudation. This exposes subendothelial collagen, triggering platelet aggregation, activation of the coagulation cascade, and formation of a thrombus. Subsequent inflammatory response leads to fibrosis and permanent occlusion of the vein. Its local anesthetic effect is due to interaction with nerve cell membranes, inhibiting sodium channels.
3. Indications & Uses
- Sclerotherapy of uncomplicated, small to medium-sized varicose veins (truncal veins, tributaries) of the lower extremities
- Sclerotherapy of telangiectasias (spider veins) and reticular veins (typically using lower concentrations)
4. Dosage & Administration
Adult Dosage: Dosage is highly individualized based on vein size, extent, and physician judgment. For 30mg/mL strength: Typically 0.5-2.0 mL per injection site for truncal veins. Maximum recommended dose per session is 2 mg per kg body weight, not exceeding 30 mL of the 30mg/mL solution (i.e., 900 mg total polidocanol).
Administration: For intravenous use only. Must be administered by a trained physician. Use fine needle (27-30 gauge). Aspirate to confirm intravenous placement before injection. Use minimal effective volume and concentration. Immediate compression and walking are advised post-procedure. NEVER administer intra-arterially. Avoid extravasation.
5. Side Effects
Common side effects may include:
- Injection site pain, burning, or itching
- Local urticaria (hives) or erythema
- Ecchymosis (bruising)
- Temporary hyperpigmentation (haemosiderin deposition) along treated vein
- Matting (development of new fine telangiectasias)
- Mild allergic reactions (skin rash)
6. Drug Interactions
| Drug | Effect | Severity |
|---|---|---|
| Other Sclerosing Agents (e.g., Sodium Tetradecyl Sulphate) | Increased risk of adverse effects if used concurrently in same session. | Major |
| Anticoagulants (Warfarin, DOACs like Apixaban, Rivaroxaban) / Antiplatelets (Clopidogrel, Aspirin) | May increase risk of bleeding/bruising at injection site. However, therapy is often continued. Decision based on individual thrombotic risk. | Moderate |
| Systemic Corticosteroids | May impair inflammatory response needed for effective sclerosis. | Moderate |
| Contraceptive Pills/HRT | Theoretical increased risk of thromboembolism. Consider pausing before elective treatment in high-risk patients. | Moderate |
| NSAIDs (Ibuprofen, Diclofenac) | Increased risk of bruising. Usually stopped 3-5 days prior to procedure. | Minor |
7. Patient Counselling
- DO wear the prescribed compression stockings for the recommended duration (usually 1-3 weeks).
- DO walk regularly after the procedure to promote circulation and reduce DVT risk.
- DO keep follow-up appointments for evaluation and possible further injections.
- DON'T take hot baths, saunas, or sunbathe the treated area for 1-2 weeks.
- DON'T undertake heavy weightlifting or strenuous exercise for 48-72 hours.
- DON'T apply topical creams or oils on injection sites without doctor's advice.
8. Toxicology & Storage
Overdose: Systemic overdose symptoms are rare but may include CNS effects (dizziness, confusion, seizures, coma), hemolysis, renal failure (from hemoglobinuria), cardiovascular collapse, and anaphylactoid reactions. Local overdose can cause extensive tissue necrosis, ulceration, or severe phlebitis.
Storage: Store below 25°C. Do not freeze. Protect from light. Keep the ampoule/vial in the outer carton. Keep out of reach of children. Discard any unused solution. The solution is for single use only; do not re-use or store opened containers.