A single sclerotherapy session typically takes 15 to 45 minutes, depending on how many veins are being treated. Most people walk out of the office and return to normal activities the same day, though the full timeline from preparation to final results stretches over several weeks or months.
What Happens During the Appointment
Sclerotherapy is an in-office procedure with no anesthesia required. You lie down, the provider cleans the treatment area, and a solution is injected directly into each targeted vein using a very fine needle. Each injection takes only seconds, and a single session can cover dozens of spider veins or a smaller number of larger veins. For someone treating a small cluster of spider veins on one leg, the appointment might wrap up in 15 minutes. If you’re treating veins on both legs or addressing larger varicose veins, expect closer to 30 to 45 minutes.
Preparation is minimal. You don’t need to fast beforehand, and most routine medications can be taken as usual. You’ll want to wear loose clothing and bring compression stockings if your provider has asked you to purchase them ahead of time.
How Many Sessions You May Need
One session is rarely enough to clear all visible veins. Most people need two to four sessions, spaced several weeks apart, to get the results they’re looking for. The exact number depends on how many veins you’re treating, how large they are, and how your body responds to the injections. Your provider will evaluate your progress after each session before scheduling the next one.
Each follow-up session is roughly the same length as the first, so you’re looking at a total time commitment of a few hours spread across several months rather than one long procedure.
Recovery and Activity Restrictions
You can walk immediately after treatment, and most people return to work the same day. However, there are a couple of restrictions that shape your first two weeks. Avoid hard exercise for two weeks after each session. Keep the treated area out of the sun for two weeks as well, or use sunscreen with at least SPF 30 if sun exposure is unavoidable.
Your provider will likely have you wear compression stockings for a period after treatment. Walking is actually encouraged in the days following the procedure because it helps blood flow redirect through healthier veins.
When Results Become Visible
Spider veins typically respond within three to six weeks, gradually fading as the treated vein collapses and gets reabsorbed by the body. Larger varicose veins take longer, often three to four months before you see the full effect. The veins won’t vanish overnight. They darken first, then slowly fade over the following weeks.
For larger veins treated with foam sclerotherapy (sometimes combined with laser treatment), closure rates are high. One study of over 2,000 treated limbs found that 98.9% of veins remained fully closed at the one-year mark.
How Long Side Effects Last
Most side effects are mild and temporary, but some take longer to resolve than people expect.
- Bruising: Common at injection sites and typically fades within a few weeks.
- Soreness: About 20% of patients experience tenderness near the injection sites for one to two weeks.
- Brown staining (hyperpigmentation): This is the side effect that catches people off guard. Dark lines or spots can appear along the treated vein and persist for 6 to 12 months. In about 1% to 2% of patients, the discoloration lasts longer than a year.
- New tiny veins (telangiectatic matting): Fine reddish veins sometimes appear near the treatment site. These typically resolve on their own within three to six months.
- Temporary swelling or hives: Localized reactions at the injection site usually fade within about 30 minutes.
The Full Timeline at a Glance
If you’re trying to plan around sclerotherapy, here’s a realistic picture. The procedure itself takes under an hour. You’ll need to limit intense exercise and sun exposure for two weeks. Spider veins fade within about six weeks, larger veins within a few months. You’ll likely return for additional sessions over the course of two to four months. And if brown staining develops, it can take up to a year to fully clear. So while the treatment is quick, the full process from first appointment to final results typically spans three to six months for spider veins and potentially longer for larger veins or multiple treatment areas.