Botulinum toxin is an injectable drug approved for the treatment of lines between the eyebrows (frown, or glabellar, lines). It’s made from the toxin of a bacteria, Clostridium botulinum, normally associated with a type of food poisoning.

Some types of wrinkles are formed when facial muscles tighten and don’t fully relax. When small amounts of botulinum toxin are injected into the affected area, the drug blocks nerve signals to the muscles. The muscle relaxes and the wrinkles become less visible. The effect is only temporary, lasting about three to six months. As the effects of the injection wear off, the wrinkle will become more visible.

Botulinum toxin injections are the most popular cosmetic procedure in the U.S. The American Society for Aesthetic Plastic Surgery reports more than 2.46 million injections were done in 2008. The average cost of an injection is about $440.

A New Competitor

The first botulinum toxin for cosmetic use was BOTOX®, approved in 2002. In May 2009, the FDA approved a new botulinum toxin for cosmetic use, called DYSPORT® (abobotulinumtoxinA). While BOTOX and DYSPORT are made from the same type of botulinum toxin, they contain different concentrations of the drug. New York City Dermatologist, Neil Sadick, M.D., has several years experience working with DYSPORT in Europe. He says one unit of BOTOX is about the equivalent of 2.5 to 3 units of DYSPORT. Thus, it takes more of the DYSPORT to produce the same results as those from BOTOX. BOTOX also appears to stay within the injected area while DYSPORT tend to disperse more within the tissues. Thus, BOTOX may be better when physicians need targeted precision. Other than those two factors, in his opinion, the two products appear to provide similar results.

Sadick anticipates that with the new competition, the price of BOTOX will come down. The choice of which product to use will most likely fall to physician preference, especially while the new product rolls out (it’s scheduled for a July 2009 product launch). Patients who haven’t responded well to BOTOX or have had mild adverse reactions to BOTOX may want to try DYSPORT as an alternative. In the meantime, Sadick hopes researchers will conduct side-to-side comparison studies to determine if one product is better or longer-lasting than the other.

Just before the approval of DYSPORT, the FDA announced that all botulinum toxin products (including BOTOX and DYSPORT) must now contain a “black box” warning label. The agency was concerned over reports of rare, but potentially serious or life-threatening problems that can occur if the drug migrates beyond the injection site. Depending upon the area injected, botulinum toxin can cause double vision, droopy eyelids, muscle loss, hoarseness, difficulty speaking, loss of bladder control, breathing troubles or swallowing problems.

For information on botulinum toxin injections and other cosmetic procedures:

American Academy of Dermatology

The American Society for Aesthetic Plastic Surgery

Physicians Coalition for Injectable Safety

American Society of Plastic Surgeons