A 38-year-old woman with primary varicose veins of the lower limbs is being considered for intervention. She has symptomatic varicose veins with recurrent leg swelling and skin changes. What is the drug of choice for sclerotherapy in this patient?

Explanation

## Sclerotherapy for Varicose Veins **Key Point:** Sodium tetradecyl sulfate (STS) is the most commonly used sclerosing agent for varicose vein treatment in India and worldwide. It is the drug of choice for both foam and liquid sclerotherapy. ### Mechanism of Action of Sclerosing Agents Sclerosants work by: 1. Damaging the endothelial lining of the vein 2. Causing thrombosis and fibrosis 3. Obliterating the vein lumen 4. Eventual reabsorption of the sclerosed vein ### Common Sclerosing Agents | Agent | Strength | Uses | Advantages | Disadvantages | |-------|----------|------|------------|---------------| | **Sodium tetradecyl sulfate (STS)** | 0.5–3% | Small to medium veins | Effective, safe, widely available | Rare anaphylaxis | | Polidocanol | 0.5–2% | Small to medium veins | Good tolerability | More expensive | | Hypertonic saline | 23.4% | Telangiectasia, small veins | Very safe | Less effective for larger veins | | Sodium morrhuate | 5% | Rarely used | Historical use | Largely replaced | **High-Yield:** Sodium tetradecyl sulfate is the **first-line sclerosing agent** for symptomatic varicose veins. It is available in multiple concentrations (0.5%, 1%, 3%) and can be used as both liquid and foam formulation. ### Treatment Algorithm for Varicose Veins ```mermaid flowchart TD A[Symptomatic varicose veins]:::outcome --> B{Vein diameter & location?}:::decision B -->|Small veins <3mm| C[Sclerotherapy with STS]:::action B -->|Medium veins 3-8mm| D[Foam sclerotherapy or endovenous ablation]:::action B -->|Large veins >8mm| E[Endovenous laser/radiofrequency or surgery]:::action C --> F[Compression stockings post-procedure]:::action D --> F E --> F ``` **Clinical Pearl:** Foam sclerotherapy (STS mixed with air or CO₂) is increasingly preferred over liquid sclerotherapy because it requires lower volumes, has better contact with vein walls, and is effective for larger varicose veins (up to 10 mm diameter). **Tip:** In NEET PG exams, when asked about sclerotherapy for varicose veins, the answer is almost always **sodium tetradecyl sulfate**. Know its concentrations (0.5%, 1%, 3%) and that compression is mandatory post-procedure. [cite:Park 26e Ch 3]