Clinical uses for botulinum toxin shine where standard therapies fail

Key Points

Lisbon, Portugal - Above and beyond its therapeutic value in cosmetic medicine, botulinum toxin can be useful in a number of medical indications and can represent an adjunct treatment option, said Philippe Humbert, M.D., Ph.D., at the 20th annual European Academy of Dermatology and Venereology Congress last October.

Both physicians and the public are well aware of the cosmetic benefits that botulinum toxin can have in skin rejuvenation treatments. The toxin can also prove useful in the treatment and/or relief of numerous medical conditions, including hyperhidrosis, inverse psoriasis, hidradenitis suppurativa, eccrine tumors and vestibulodynia, says Dr. Humbert, professor and head of the department of dermatology, University Hospital, Besançon, France.

"The common denominator of many dermatologic conditions and diseases is increased sweating, which in many cases can significantly aggravate the affected skin region, particularly in the folds of the skin. Treatments with botulinum toxin can at least temporarily minimize the sweating, subsequently resulting in an improvement of the local symptoms, which often can offer a great relief in affected patients," Dr. Humbert says.

According to Dr. Humbert, botulinum toxin treatments are very useful in treating dermatologic conditions associated with profuse sweating in the skin folds (axillary, inguinal and palmar and plantar hyperhidrosis). Other conditions associated with increased sweating in the folds with subsequent skin maceration and localized pain include inverse psoriasis, Hailey-Hailey disease (benign familial pemphigus) and Darier's disease.

Many of these conditions are challenging to treat, manage and control, Dr. Humbert says, and disease flare is sometimes aggravated by increased localized sweating (particularly in the fold areas). "I believe that for these dermatoses, botulinum toxin treatments should not be used as a monotherapy but instead used in combination with more conventional therapeutic approaches. Alleviating and/or stopping the localized increased sweating can offer a better milieu for the affected skin regions to heal," Dr. Humbert says.

Botulinum toxin treatments could be performed approximately every six months, which is very similar to the treatment protocols seen in cosmetic medicine. The doses of botulinum toxin used vary, Dr. Humbert says, depending on the type of toxin used and the severity of disease.

"It must be said that these indications are off-label and do not offer a cure for the patient," he says. "As such, the physician has the difficult task to establish that improvements achieved are due to the botulinum toxin treatment. Therefore, as these are symmetrical diseases, I would suggest to treat one side of the patient first and observe the therapeutic benefit, and if there is a good response, one can proceed to treat the other side. This approach helps to establish the treatment efficacy of the toxin in that particular disease and patient."

Neurologic know-how

Botulinum toxin treatment can also find utility in conditions and diseases that have a neurologic component, such as anal fissures, vestibulodynia, lichen simplex and notalgia paresthetica, Dr. Humbert says.

Traditionally, anal fissures were surgically treated, he says, but the toxin approach antiquates the need for surgery. A one-time injection of 20 units of botulinum toxin will often suffice to close the fissure within only a few weeks to a few months time.

Vestibulodynia can be a very debilitating condition characterized by chronic pain of the vulvar region, and it occurs without any identifiable cause or visible pathology. Patients will complain of severe pain every time they have contact with the vulvar area, and here, botulinum toxin can help to alleviate symptoms, Dr. Humbert says.

Dr. Humbert has treated more than 30 patients with botulinum toxin for this condition, and he has achieved good outcomes regarding pain relief. At the three- and six-month follow-up after a 100 unit botulinum toxin treatment, he says he found that the pain was significantly reduced in his patients.

Disclosures: Dr. Humbert reports no relevant financial interests.