Will Botulinum Toxin (Botox) Injections Help Me?
Abnormal foot posturing and leg spasms which impair walking (foot dystonia), eye twitching or involuntary eye closure (blepharospasm), and drooling are usually greatly improved with botulinum toxin injections while conventional oral medications are usually poorly effective for these disabling symptoms.
- Abnormal posturing of the foot and toes (sometimes associated with painful leg spasms) is called foot dystonia, and commonly occurs in patients with Parkinson’s disease in the early morning, when medications wear off, or with exercise.
- Drooling or excessive saliva production can be embarrassing, impair speech and social communication, as well as soiling clothes.
- Eye twitching or involuntary eye closure (blepharospasm) impairs reading, driving, and social communication by essentially causing functional blindness.
Botulinum toxin is injected specifically into the overactive muscles causing either the foot cramps, eye twitching or drooling (salivary glands). The effect comes on gradually over several days, with the peak effect reached in approximately 2 weeks. The results last for about 3 months, so injections are repeated at 3 month intervals to maintain ongoing benefits.
Without treatment, the symptoms will continue and gradually worsen, resulting in increased disability.
Oral medications can occasionally be helpful for foot dystonia, and deep brain stimulation is usually an effective treatment. Botulinum toxin injections are less invasive than deep brain stimulation and have a high success rate for foot dystonia.
Blepharospasm is rarely improved with other treatments, unless it occurs solely as a consequence of anti-Parkinson medication wearing off. In such circumstances, adjustment of oral anti-Parkinson medications can often be effective, but even then, botulinum toxin injections provide additional therapeutic benefits. Deep brain stimulation, on the other hand, may itself induce involuntary eye closure (blepharospasm) in about 10 or 15 percent of patients, and thus is not recommended for treatment.
Drooling in Parkinson’s disease is caused by reduction in automatic swallowing mechanism, resulting in pooling of saliva in the mouth. Although oral medications to dry up secretions can sometimes be of some benefit, these are commonly associated with significant adverse effects, including worsening of cognition. Botulinum toxin injections are generally much more effective, and have a much lower rate of side effects.
Prognosis With Treatment
Botulinum toxin injections for foot cramping and abnormal posturing (foot dystonia) results in reduced pain, improved foot positioning and improved quality of gait. Side effects are uncommon, but can occasionally include increased calf weakness. Injections are customized in terms of dose and the specific muscles injected, to maximize benefit and minimize excessive weakness.
For drooling (sialorrhea), botulinum toxin injections are targeted to the parotid and submandibular glands. 80 to 90 percent of patients experience improvement or elimination of drooling, resulting in improvement in speech and elimination of embarrassment and soiling of clothing. Side effects can include excessively dry mouth and, rarely, increased trouble swallowing. We commonly use Myobloc instead of Botox in order to more selectively reduce drooling, and reduce any risk of worsening of swallowing.
Eye twitching or involuntary eye closure (blepharospasm) occurs in up to 10 to 20 percent of patients with Parkinson’s disease. Botulinum toxin injections result in marked improvement in 80 to 90 percent of patients. Occasional side effects include eye dryness and eyelid droopiness. The specific dose and pattern of injections around each eye is customized to maximize benefits and minimize any potential adverse effects.