Sclerotherapy: How injections help treat spider veins and varicose veins

Veins that curl just under the skin can be a nuisance—leg visibility, discomfort, or a sense that you’re fighting the clock with every step. If you’ve ever wondered how doctors actually tackle those spider veins or the stubborn varicose varieties, sclerotherapy is a term you’ll hear a lot. It’s a medical procedure, not a skin cream or a cosmetic laser trick. Here’s the down-to-earth, practical guide to what it is, how it works, and what to expect.

Okay, what exactly is sclerotherapy?

Sclerotherapy is a medical treatment designed to address spider veins and varicose veins by directly targeting the problematic veins. In concrete terms, a clinician injects a sclerosant—a chemical irritant—into the vein. This irritation makes the vein’s walls stick together and collapse. Over time, the body reabsorbs the treated vein, and the visible thread or bulge fades or disappears. It’s a targeted intervention, not a broad skin treatment, which is what sets it apart from things like exfoliation or cosmetic laser therapy.

How does it actually work, under the hood?

Think of a vein as a plumbing tube. When you inject a sclerosing agent into it, you’re deliberately nudging the lining of that tube to become inflamed. The inflammation makes the vein close off, so blood is naturally rerouted through healthier, deeper veins. Over weeks to months, the treated vein is gradually reabsorbed by the body and ceases to be a functional part of the circulation. Some clinics use foam sclerosants, which are more foamy and give the solution more surface contact with the vein wall. For larger, deeper veins or more complex patterns, doctors might use ultrasound guidance to pinpoint exactly where to inject. It’s a bit of a precision art—accurate mapping, exact injections, and patient comfort all matter.

Who benefits from this approach?

Sclerotherapy shines for two main groups:

• Spider veins: those tiny, web-like networks you might notice on the legs or ankles. They’re usually cosmetic concerns, but occasionally they can cause itching or burning sensations.

• Varicose veins: the larger, ropey veins that can swell or ache after you’ve been standing for a while. For many people, improving the appearance also reduces the heaviness or aching that comes with more pronounced varicose disease.

Not everyone is a candidate, though. If you’re pregnant, have a history of blood clots, a deep vein thrombosis, an active infection in the treatment area, or certain bleeding disorders, your clinician will weigh risks and benefits differently. Allergies to sclerosants or sensitivity to injections are also important considerations. A thorough evaluation, usually including a leg exam and sometimes venous mapping with ultrasound, helps determine whether sclerotherapy is the right path.

What happens during a session?

A typical session is fairly straightforward, especially for spider veins. Here’s a rough idea:

• Preparation: You’ll wear medical-grade stockings or compression garments, and the treated area is cleaned. The clinician reviews your medical history and explains what they’ll do.

• The injections: Using a fine needle, the doctor injects the sclerosant directly into each affected vein. For a larger vein or more extensive network, several injections may be needed in a single visit.

• Comfort and duration: The injections themselves feel like tiny pinpricks. Some people experience a light burning sensation, but most find it tolerable. A session for smaller veins may take 15–45 minutes; treating larger or many veins can take longer.

• Post-treatment care: After the injections, you’ll likely wear compression stockings for a period and resume normal activities gradually. You’ll be instructed on movements or activities to avoid briefly—think of it as a short pause rather than a full halt.

The aftercare piece is surprisingly important

You don’t just walk out feeling “finished.” The body needs time to respond. Most patients notice visible changes within a few weeks, though a few may see gradual improvement over several months. It’s common to require more than one session to achieve the best results, especially with larger varicose veins or a broader network of spider veins.

Compression is your new best friend here

Compression stockings aren’t just a fashion choice; they’re a practical ally in sclerotherapy. They help keep the treated veins compressed, support blood flow in the surrounding vessels, and can reduce minor bruising or swelling. The exact duration varies by the clinician and the patient, but many people wear compression garments for about a week to a few weeks after treatment.

What about risks and realities?

No medical procedure is entirely risk-free, but sclerotherapy is considered safe when performed by trained clinicians. Common, temporary side effects include:

• Bruising at the injection site

• Mild swelling or a feeling of fullness

• Skin color changes around the treated area (usually fades over time)

• Light burning or aching that resolves quickly

Less common but more serious risks can occur, such as skin ulcers, blood clots in unusually rare cases, or inflammatory reactions. That’s why the selection of patients, the technique used, and proper aftercare matter.

A quick compare-and-contrast with other vein treatments

• Sclerotherapy vs laser therapy: Both aim to close off varicose or spider veins, but the approach differs. Sclerotherapy uses direct injections to irritate the vein lining, while laser therapy uses targeted heat delivered from outside the skin. For some veins, laser therapy might be preferred if injections aren’t ideal, but for others, sclerotherapy can be more efficient or accessible.

• Surgery vs non-surgical options: In the past, some varicose veins required surgical stripping. Today’s minimally invasive approaches—like sclerotherapy—often offer similar or better results with less downtime. There’s no one-size-fits-all answer, and the decision typically hinges on vein size, location, symptoms, and patient preferences.

Should you consider it? Questions to ask your clinician

If you’re weighing this option, here are practical questions that help you decide in a calm, well-informed way:

• How large are the veins we’re treating, and how many sessions might I need?

• What sclerosant will be used, and is ultrasound guidance available if needed?

• What downtime should I expect, and what activities should I modify?

• What are the potential side effects in my case, and how are they managed?

• What are the signs that I should contact the clinic after treatment?

Safety and the path to a good outcome

Choosing the right clinician is crucial. Look for board-certified vascular specialists or dermatologists with specific vein-treatment training. Clinics that use ultrasound mapping for larger veins tend to offer higher precision and safer outcomes. Don’t hesitate to ask about the clinician’s experience with sclerotherapy, the sclerosants they prefer, and their protocol for post-care follow-ups.

A few friendly reminders for those in the know

• It’s a targeted therapy: It’s not a skin-clearing technique. The focus is the vein itself, not the surrounding skin.

• Time and patience matter: Vein disappearance takes weeks, and multiple sessions may be needed for optimal results.

• Realistic expectations help: Some veins, especially deep or large varicose veins, may not vanish completely. The goal is often significant improvement in appearance and symptoms.

A broader view for curious minds

Sclerotherapy sits at an interesting crossroads of aesthetics and vascular health. It’s a practical example of how medicine can blend cosmetic improvement with functional relief. When you think about the body’s plumbing, it’s easier to appreciate why closing off a troublesome vein can make a real difference in how someone feels day-to-day. It’s not magic; it’s a careful, repeatable process that combines anatomy with precise technique.

If you’re exploring topics that frequently appear in state board curricula, sclerotherapy is a clear case study in minimally invasive vascular care. It illustrates how doctors assess a vascular network, select the right intervention, and manage post-treatment healing. The approach also highlights the importance of patient education—explaining what to expect, what the risks are, and how to care for the body after a procedure.

A closing thought

Vein health rarely makes headlines, but it quietly influences comfort, mobility, and confidence. Sclerotherapy offers a straightforward path to less visible veins and a lighter leg experience for many people. If you’re curious about the science or considering options, talk to a qualified clinician who understands the anatomy, has hands-on experience, and can tailor the plan to your unique situation. After all, the best treatments aren’t just technically sound—they’re thoughtfully matched to the person receiving them.

In the end, sclerotherapy is more than a procedure name. It’s a practical, evidence-based approach to a common vascular concern—one that keeps the focus firmly on safer, simpler, and tangible improvement. If veins are on your radar, you’re far from alone, and the right information can make all the difference.