I was asked last week by a patient why Botox was being used for heavy sweating. I agreed with him that it is not so intuitive… He, himself, suffers when having to give presentations at his firm because under a slight stress, his underarms get wet; he feels it gives the wrong impression (being nervous, not confident, worried, etc.) to the clients he is trying to bring in to his firm. He will therefore wear layers of clothes, which adds to the “body heat”. So here is my answer.
Excessive sweating – aka hyperhidrosis – of the underarms, hands and feet can be uncomfortable, both physically and socially. We’ve all shaken hands of someone suffering from this medical condition. You can also be sure that the person suffering from this also hates having to shake clients’ hands or give presentation with his/her arms up: teachers, lawyers, bankers, CEOs, gym coaches, etc.
Sweat glands happen to be stimulated by the same neuromodulator (called acethylcholine) as the one stimulating the muscles to contract, hence Botox works as a “blocker” for both sweating and muscle contractions, respectively weakening sweat production and wrinkle formation.
Many topical treatments have been offered over the years to treat hyperhidrosis such as deodorants, anti-perspirants, etc. Unfortunately, many topical treatments contain aluminum and can be irritative.
Surgery has also been performed such as liposuction to the underarm, but this seems to work only for some time after which, the heavy sweating returns. Not only this is not always efficient, liposuction to the underarm region must be done very carefully as the main trunks of nerves and blood vessels to the hands are found just below the armpit skin and could be injured.
Another surgery called ETS – endoscopic thoracic sympathetectomy – is quite invasive and will only be done occasionally for heavy sweating of the hands. This surgery involves going into the chest cavity with instruments and camera to try to divide the nerves (sympathetic system) around the main thoracic blood vessels that bring innervation to the hands. Quite invasive and it does not always work.
Botox “therapeutic” was approved several years ago, both by the FDA and Health Canada for the treatment of heavy sweating.
When used for hyperhidrosis, Dr. DuPéré likes to apply a topical anesthetic cream over the skin area to be treated after which, several small injections in the dermis are performed. It is a relatively fast treatment and the effects will appear usually within 3-7 days. Results can last up to 12 months, the average being 6-9 months in my experience. Women tend to require 50 units per side whereas men often receive 100 units per side.
Side-effects are usually local where patients will have tenderness and some visible welts for a few days, same as one would see with mosquito bites or allergy testing.
When doing hands and feet, Dr. DuPéré will often add wrist or ankle local anesthetic blocks as the skin over the fingers and toes are more sensitive than the underarm region.
For complicated cases of hyperhidrosis, there is a “starch” test Dr. DuPéré can perform to identify precisely where the sweat glands are located, if unclear.
Finally, many drug plans and insurances will cover the medication part of the treatment, or a part of it, which can be advantageous to patients.