Sclerotherapy or injection treatment of varicose and spider veins is a non-surgical treatment. The injections are relatively painless – they feel much like the stinging of mosquito bites.

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During treatment, a sclerosing solution is injected into the varicosity, dilated vein or network of spider veins. The sclerosing agent irritates the walls of the vein, causing it to go to spasm. The vein walls stick together, sclerose and over a period of a few weeks, the vein starts to fade and eventually disappears. This causes closure of the vein so normal blood circulation is taken over by healthy veins.

A single sclerotherapy treatment session involves multiple injections. The number of treatment sessions will vary, depending on the number and size of veins treated the necessary healing time, and the level of cosmetic expectation desired.

Treatments are usually performed every one to two weeks. The total number of treatments will vary between patients, but can be as short as 1-2 visits, or require over 15 visits, but the average is 4-6 visits. The larger veins are treated first, then the smaller veins afterward.

Sclerotherapy doesn’t eliminate hereditary tendency to develop varicose or spider veins. Patients may, therefore, notice some new but different veins in the future.

Sclerotherapy Effectiveness

Although this procedure works for most patients, there are no guarantees for success. 50%-80% of injected veins may be eliminated with each session of sclerotherapy.

Less than 10% of the people do not respond to the injections at all. In these instances, different solutions can be tried.

In general, spider veins respond in three to six weeks, and larger veins respond in three to four months. If the veins respond to the treatment, they will not reappear. However, new veins may appear at the same rate as before. If needed, you may return for injections.

Side Effects of Sclerotherapy

  • Itching (which can last for one or two days)
  • Raised, red areas at the injection site (should disappear within a few days)
  • Bruising may also occur around the injection site (can last several days or weeks)
  • Temporary brown lines or spots (in about 5% of cases) may occur at the vein site(take weeks to a year to fade)
  • Neovascularisation — the development of new, tiny blood vessels — may occur at the site of sclerotherapy treatment (can appear days or weeks after the procedure, but should fade within three to twelve months without further treatment.
  • Veins may become darker and then fade in a few weeks
  • Veins may be tender for 7 days
  • A small ulceration may occur and heal with a scar
  • In extremely rare cases, allergic reaction to the solution used, thrombophlebitis, deep vein thrombosis (blood clot in leg) and pulmonary embolism (blood clot in the lung) and arterial injection may occur.
  • Should any of the following side effects occur, contact your physician immediately. These include: inflammation within five inches of the groin, a sudden onset of a swollen leg, formation of small ulcers at the injection site.
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Frequently Asked Questions

  • Eat a snack 1 hour prior to your treatment
  • Do not shave legs for 2 days prior to and the day of your appointment
  • Do not apply creams or oils the night before and the day of treatment (interfere with adherence of the tapes to the skin, and can result in more bruising).
  • Avoid self-tanning creams (the tapes we use to secure the cotton balls may cause temporary discoloration of the artificial tan)
  • Avoid hot baths and whirlpools (these cause further enlargement of the vein)Medications: Prior to sclerotherapy, certain medications should be avoided. Please follow these guidelines:
  1. Tetracycline or Minocin, both antibiotics, may possibly cause a staining of the skin if taken 7 to 10 days before or after sclerotherapy. Ask your doctor about other antibiotic medications you may take, or ask for safe guidelines for discontinuing these medications. If you are required to take an antibiotic before any invasive procedure, such as dental procedures, colonoscopy or surgery, please inform your physician.
  2. Do not take aspirin, ibuprofen (i.e. Advil) or other anti-inflammatory medications for 48 hours before and after sclerotherapy, because these medications may interfere with the action of the sclerosing agent or increase bleeding. Tylenol is permitted. Ask your doctor for specific guidelines before discontinuing any medication.
  3. Prednisone decreases the effectiveness of the sclerosing agent. Ask the doctor who prescribed your prednisone if it can be safely discontinued for 48 hours before the sclerotherapy procedure.
  • Bring shorts to wear during the procedure
  • Wear slacks or dark hose to hide the cotton balls (that are taped on for a few hours after the treatment)
  • If you have compression hosiery (support stockings) and tensor bandage from previous treatments, please bring them with you so we can make sure they are still good and they will provide adequate support after the procedure.
  • Remove the cotton balls 2-3 hours after treatment. You may notice sticky tape marks on your legs. These can be easily removed with adhesive remover, nail polish remover or baby oil.
  • Continue your normal routine. Walk for 30 minutes outside or on a treadmill
  • Avoid hot baths, hot showers, alcohol and aspirin, ibuprofen for 48 hours, unless you are taking aspirin for a heart condition.
  • You may apply moisturizing lotion after 24 hours
  • Avoid tanning beds for at least 2 weeks. You may get an irregular tan, but it is not harmful
  • Apply sunscreen liberally when exposed to natural sunlight for 2 weeks after treatment
  • Wait 1-2 weeks for your next sclerotherapy treatment
  • If prescribed, wear elastic support stockings or bandages.
  • Please avoid prolonged periods of immobility on the day of treatment such as long naps or long car drives. Do not schedule any air flights for 2 weeks after your treatment. Do not schedule any overseas flights for 3 weeks after treatment.
  • You will NOT notice an immediate improvement.  Clearance usually occurs over a 2-week period and in some patients may take up to 8 weeks. There may only be a partial response after the first one or two treatments.
  • The spider veins may initially turn darker red after treatment and go through different colors or the bruises. This is part of the normal healing response.
  • After treatments are completed, you should return for several maintenance treatments anywhere between 6 months to 1 year later.
  • You may notice small bumps or darkening of the veins. This is temporary and should gradually resolve.
  • Follow all instructions above
  • Avoid high impact activities for 48 hours: example: running, aerobics, heavy weight lifting
  • If prescribed, wear elastic support stockings or bandages. Leave the tensor bandage on for 48 hours. Use compression stocking (at the top of the tensor bandage) all day for 7 days). Remove compression stockings at night.


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