The same Botox used to wipe out wrinkles may also soothe stiff, rigid muscles after a stroke.

A new study shows that repeated Botox injections after a stroke may improve muscle tone and reduce pain in the hands and arms, making it easier for stroke patients to dress themselves and perform other daily activities.

Researchers say up to 30 percent of stroke patients suffer from disabling muscle tightness, a condition known as muscle spasticity. When muscle spasticity affects the arms and hands, it makes it difficult for stroke patients to dress, wash, or feed themselves, and carry out other normal tasks.

"If it isn't managed effectively, post-stroke spasticity can result in very disabling complications such as contractures, a condition that leaves the muscles and tendons permanently shortened," says researcher Allison Brashear, MD, in a news release. Brashear is a professor and chairwoman of neurology at Wake Forest University Baptist Medical Center.

"Early intervention with effective therapies is absolutely vital to prevent the profound disability that afflicts many stroke patients, and to lessen the emotional and financial toll on caregivers and the health care system as a whole," says Brashear.

What Is a Stroke? Get the Facts

Botox for Muscle Spasticity

Previous studies have shown Botox injections reduced short-term muscle spasticity and pain after stroke, but researchers say this is the first study to look at the long-term effects of the treatment.

In the study, presented at the Annual Meeting of the American Association of Physical Medicine and Rehabilitation in Philadelphia, researchers treated 279 stroke patients with muscle spasticity in their arms and hands with up to five Botox injections delivered over the course of a year. Botox was injected at the wrist, thumbs, fingers, and elbows to block overactive nerve impulses that trigger excessive muscle contractions.

The results showed that after six weeks of treatment, muscle tone in the affected areas was improved and the improvement was sustained throughout the study.

Researchers also measured functional disability in four areas at the start of the study (hygiene, dressing, limb posture, and pain) on a four-point scale from “no disability” to “severe disability” and asked participants to identify which area was most important to them.

The study showed that at least 50 percent of stroke patients experienced a one-point improvement in their targeted area.

"The treatment resulted in sustained and meaningful functional improvement that makes a difference in the daily lives of stroke patients and the people who care for them," says Brashear.

Seven percent of the participants reported side effects of the Botox treatment, including headache, pain in the arm, or a flu-like illness.

Researchers say the results suggest that Botox may provide relief from poststroke spasticity with fewer side effects than currently available oral drugs, which are associated with side effects such as sedation, mental confusion, dizziness, and muscle weakness.

The study was funded by the pharmaceutical company Allergan Inc., which developed Botox (botulinum toxin type A, BoNTA).

By Jennifer Warner, reviewed by Louise Chang, MD

SOURCES: 2005 Annual Meeting of the American Association of Physical Medicine and Rehabilitation, Philadelphia, Oct. 28, 2005. News release, Wake Forest University Baptist Medical Center.