Botox Injections for Wrinkles

Botulinum Toxin

Botulinum toxin is produced by the bacterium Clostridium botulinum. There are eight distinct types of botulinum, seven of which are associated with paralysis. The bacteria can cause botulism through ingestion of contaminated food or infection of a wound, producing symptoms including muscle weakness, gastrointestinal distress, dilated unreactive pupils, and dryness of mucous membranes.

The nerve-blocking, muscle-relaxing actions of the toxin have been successfully applied therapeutically, however. Today the use of botulinum toxin is now FDA approved for the treatment of many conditions including wrinkle reduction, certain types of facial paralysis, spasms, and other nerve disorders, and it is currently under investigation for the treatment of headaches and pain syndromes. Its most common use by far, however, is for the cosmetic treatment of wrinkles.

Botox for Wrinkles

In the late 1980s, a group of physicians at Columbia University noticed that patients who received injections for nerve disorders also experienced cosmetic improvement. They pursued this investigation and soon developed the Botox therapy in common use today. Because they saw the benefits of Botox injections for cosmetic purposes, physicians safely used the therapy in an "off-label" application (legal because it was FDA approved for other purposes), for years. Finally, the FDA approved the use of Botox for wrinkle reduction in April 2002.

Botox is a purified form of type A botulinum toxin. When injected into wrinkles, tiny amounts of botox relax the surrounding muscles. This has the effect of smoothing the skin so that the wrinkles disappear. Botox injections are effective for wrinkles in the forehead, lower eyelids, side of the nose, and for frown lines, crow's feet, and above the lip. They may even be used in the neck.

Safety and Side Effects of Botox

Injected botox does not cross the blood-brain barrier, and the only side effects are temporary muscle weakness near the injection site. Treatments may slightly hamper patients' ability to squint or frown, or may cause the corners of the mouth to turn down.

Dosages used for therapeutic injections are very low, with a wide safety margin assured. Since a small percentage of patients (5-15%) may become nonresponsive to Botox due to formation of neutralizing antibodies, newer forms of Botox are being developed and tested. (Dysport is a similar botulinum toxin type A preparation available in Europe, and Myobloc is a type B preparation now under study.)

Are Wrinkle-Reducing Effects Permanent?

While Botox injections effectively reduce facial wrinkles, their effects do not last permanently. Patients can expect the effects to wear off after several months. Repeated treatments are safe and effective.