The many faces of botox

Before botox came along, many of us were familiar with the botulinum toxin as a cause of the deadly botulism food poisoning. Yet, the same mechanism that makes the toxin lethal – muscle paralysis – also grants it curative powers. Botox, or Botulinum toxin type A, works by preventing the release of acetylcholine, a neurochemical essential for muscle contraction. Injected locally, Botox can prevent individual muscle contractions.

Today, most Botox injections are aimed at minimizing further lines between the eyes (glabellar lines), but they’re also proving useful for treating more serious medical conditions. So far, Botox is FDA-approved only for glabellar lines, certain eye problems, facial pain, and debilitating neck and shoulder pain. Even so, doctors may prescribe it "off-label" that is, for conditions other than those for which it was originally approved.

Whether it’s used for cosmetic or medical purposes, a Botox treatment usually wears off in a few months, so repeat injections are an expected part of therapy. Doses are adjusted according to a person’s weight, the severity of pain, and the size of muscle being injected. With regular injections, the muscle may atrophy and lose some of its function, so the time between treatments may increase.

Here are some applications for Botox beyond its cosmetic use.

Chronic Headaches

Botox is under study as a treatment for chronic headaches, especially tension headaches and migraines. A tension headache is often brought on by stress-induced muscle tightness that causes mild to moderate pain across the forehead, at the back of the head, or throughout the head. Migraines tend to produce pulsating or pounding pain on one side of the head and may be accompanied by nausea, sensitivity to light or sound, or visual disturbances.

How Botox helps: Experts believe Botox works in at least two ways – by suppressing the muscle contractions that trigger tension headaches, and by interrupting nerve transmission of pain signals to the brain.

The evidence: Researchers began to study Botox for headaches after migraine patients getting cosmetic injections reported having fewer headaches. Several studies reported in a recent meeting of the American Headache Society suggest that botulinum toxin is living up to its promise. One large study found that Botox injections given at three-month intervals for an average of nine months reduced the frequency or intensity of headaches in 80 percent of the 271 patients. Before the study, all had tried at least three types of oral medications that either didn’t work or had unacceptable side effects.

Researchers at the headache meeting also presented positive results for Botulinum toxin type B (Myobloc), which has a slightly different chemical structure but can be used to treat many of the same conditions, especially neck spasms. Many doctors remain more comfortable with Botox, however, because it’s been studied longer.

Botox is not yet FDA-approved for treating headaches.

Eye Conditions

Strabismus occurs when either the inner or outer eye muscle is weak and the opposite muscle overcompensates, sometimes causing double vision or other focusing problems. Blepharospasm is a disorder in which eyelid spasms squeeze the eye shut. This condition can leave a person functionally blind.

How Botox helps: For strabismus, doctors use Botox to paralyze the overcompensating muscle. Patients who have already had surgery to correct strabismus may also benefit from Botox. For example, injections can remedy a surgical overcorrection that caused a formerly outward-drifting eye to drift inward instead.

For blepharospasm, multiple injections into the muscles around the eye can prevent it from contracting and squeezing shut. The injections may be painful, but doctors say most patients are willing to put up with the pain to be rid of blepharospasm’s debilitating effects.

The evidence: Botox has been studied for two decades as a treatment for strabismus and blepharospasm and is FDA-approved for both.

Muscle Spasms

Spasms – involuntary muscle contractions – cause many conditions, including:

• Dystonia, a neurological disorder in which muscles contract sporadically, causing painful movements and postures. Neck spasm (cervical dystonia) is a typical example.

• Hemifacial spasm, an uncommon condition characterized by grimacing and twitching on one side of the face. Once considered a psychological problem, it’s now attributed to irritation of the facial nerve.

• Esophageal achalasia, muscle spasm of the esophagus (the tube that carries food from the mouth to the stomach). It causes pain, trouble swallowing, and getting food from the mouth to the stomach, and regurgitation.

How Botox helps: Botox injections stop the spasms. In the case of esophageal achalasia, a doctor must insert a fiber-optic tube into the esophagus in order to inject the toxin into the lower esophageal muscle.

The evidence: Botox is FDA-approved for hemifacial spasm and cervical dystonia. Researchers are studying its use in esophageal achalasia.

Rectal Fissures

Splits in the skin of the anus can cause chronic pain and disability while activating spasms in the rectal muscles that interfere with healing. Anal fissures may result from childbirth or strained bowel movements.

How Botox helps: The accepted treatment has been surgical cutting of the affected muscle, but this procedure can lead to fecal incontinence. Botox paralyzes the rectal muscles long enough for the fissures to heal, so cutting isn’t necessary.

The evidence: Several studies have shown that Botox helps heal anal fissures, but its success rate varies considerably. Some doctors think that accuracy in needle placement accounts for the variation while others attribute it to differences in patients. Botox is less effective with fissures that have lasted more than two years. The FDA has yet to approve Botox for this use.

Excessive Sweating

About two percent of people suffer from hyperhidrosis, a condition that causes constant, excessive sweating. Hyperhidrosis sometimes runs in families, and illness or certain medications may also cause it. The areas most affected are the armpits, hands, feet, face, and scalp.

How Botox helps: Acetylcholine activates sweat glands. Botox injections in the armpits, palms, and soles of the feet inhibit the release of acetylcholine from nerve endings in the skin near the sweat glands. Each treatment requires multiple injections.

The evidence: The treatment often eliminates excessive sweating under the arms. Sweating palms get less complete relief. Most hyperhidrosis sufferers will need Botox injections every six to 12 months.

Other Uses

Clinicians are also using Botox to treat spastic leg and arm movements related to central nervous system disorders, certain jaw problems, laryngeal spasm and dysphonia (difficulty in making speech sounds because of abnormal muscle contractions), and excessive saliva secretion (ptyalism).

Yes, the toxin best known for erasing facial lines is also a promising treatment for many hard-to-treat medical conditions.