When choosing which sclerosing agent to use for a particular patient, Dr. Sadick, clinical professor, department of dermatology, Weill Medical College of Cornell University, New York, says he considers these factors:
"The best product for a given patient is a product that you have the most experience with and one that has a low complication profile, high safety and is FDA-approved," Dr. Sadick says.Asclera (polidocanol, Merz) and Sotradecol (sodium tetradecyl sulfate/STS, AngioDynamics) both have FDA approval. Asclera is approved for spider veins of less than 1 mm and reticular veins ranging in diameter from 1 mm to 3 mm, and Sotradecol is FDA-approved for all small, uncomplicated varicose veins of the lower extremities.
Studies show that there is an equivalency of non-inferiority of Asclera and Sotradecol. "They are both very good agents," Dr. Sadick says. "However, there is some (speculation) that polidocanol may be associated with less ulcerogenic potential."
COMPARING OPTIONS Asclera has been available for 40 years, but it wasn't approved by the FDA until 2010. "It took a really long time for the company to get approval. The studies were very extensive; the FDA had a lot of questions," Dr. Sadick says.
Two of the main advantages of polidocanol are that it is painless upon injection, and small amounts of intradermal injection are not associated with necrosis. Disadvantages include the possibility of transient urticarias. In addition, it has one-third the potency of STS and is not recommended when peripheral arterial disease is diagnosed or if patients are poly allergenic, Dr. Sadick says.
Other notable characteristics that should be factored in when considering polidocanol are that it has an extremely low incidence of allergic reactions ranging from a likelihood of 0.01 to 0.03 percent, it has hypersensitivity potential similar to STS, and it is contraindicated in patients receiving disulfiram due to the fact that it contains a small amount of ethyl alcohol in its solution. Polidocanol also has minimal potential for extravasation necrosis.1
Sotradecol, which is FDA-approved for small, uncomplicated varicose veins of the lower extremities, is the gold standard, according to Dr. Sadick. It received FDA approval in 1946 for varicose veins and telangiectasia, and it is available in 1 percent and 3 percent solutions in 2 mL vials. It has a minimal complication profile with extremely low incidence of allergic reactions ranging from 0.2 to 0.3 percent. Additionally, Sotradecol has a hyperpigmentation rate ranging from 5 to 30 percent, and its incidence of extravasation necrosis is slightly above polidocanol's.
"STS is minimally allergenic, has high versatility and a low complication profile, and it is relatively painless and has a history of good empirical data," Dr. Sadick says.
Disadvantages associated with STS are that it is painful on extravasation, tissue necrosis is possible depending on the concentration used, and it should be used with caution in allergenic patients, he adds.