Botulinum toxin used in tiny doses

Botulinum toxin is among the most poisonous substances known. Yet not all forms of the toxin are something to beware. A purified form of botulinum toxin — Botulinum Toxin Type A, trade name Botox — is being used by physicians to improve voice disorders, smooth wrinkles and treat a variety of other medical and cosmetic conditions.

“Physicians are finding more and more uses for Botox,” explains Dr. Daniel Berg, director of dermatologic surgery at UW Medical Center. “It may be an option to surgery or, in some instances, be the only effective treatment available.”

Botulinum toxin is produced by a bacteria, Clostridium botulinum. Botulism poisoning occurs when a person eats food contaminated by this bacteria or has a cut that becomes infected with it. While botulism poisoning can be life-threatening, a tiny amount of purified botulinum toxin can offer therapeutic benefits. The dosage of botulinum toxin used for medical treatment is much smaller than the amount that causes botulism. Berg notes that while a lethal amount of botulinum toxin is approximately 2,700 units, only about 20 to 25 units of the toxin are used for most treatments.

“If used correctly and in very minute doses, Botox is a safe, effective treatment option,” Berg notes.

Botox works by temporarily paralyzing targeted muscles. It is administered by injection directly into the affected muscle, where it attaches to nerve endings. The toxin then blocks the release of neurotransmitters in the brain that signal muscle contraction.

Botox was first introduced in the 1980s for treating muscular problems with the eyes such as crossed eyes, lazy eyes, uncontrolled blinking and squinting. Today, physicians are discovering a number of additional uses.

Conditions treated with Botox include dystonias (illnesses associated with abnormal, involuntary muscle movements) affecting the larynx (spasmodic dysphonia), neck (spasmodic torticollis), eyelids (blepharospasm) and head and neck (oromandibular dystonia). It is also used to treat abnormal conditions associated with cerebral palsy, recovered facial nerve injuries and even writer’s cramp.

Most recently, Botox has gained popularity as a cosmetic treatment for frown lines and crows’ feet — wrinkles caused by the contraction of muscles. And it can be used to treat troublesome sweating.

“There are a variety of diseases related to muscle control activity,” explains Dr. Allen Hillel, an associate professor of otolaryngology at the School of Medicine who uses Botox at UW Medical Center. “Botox is a remarkable drug for treating a number of these problems.”

Results from Botox treatment are noticeable within two to four days following the injection. Since the effects of treatment are temporary, injections must be repeated as needed (every two to eight months, approximately). Costs for Botox treatments depend on the amount of toxin used.

“For many people, treatment with Botox is well worth the investment,” Berg says. “Compared to surgery or not being able to function well in daily life, Botox is worth it.”

Side effects for treatment with Botox vary depending on its use. Those treated for frown lines, for instance, may experience a slight drooping of the eye. In most cases, Botox is not recommended for use by pregnant or nursing women. Berg stresses that all patients should receive Botox treatments from qualified physicians and be sure to inquire about any specific side effects. ¶ Julie Rathbun