Intradermal injections may cause a tiny, short-lived bleb. When intradermal injections are not possible due to skin thickness, one may perform superficial subcutaneous injections. Be aware that these injections sometimes lead to a small bump. Very minimal bleeding can be visible and this may be helpful in marking prior injection sites. Significant bleeding should not occur. However, if it does, pressure on the site quickly stops the bleeding.
Patients can walk out of the office soon after the procedure. Use caution if using a foot block (especially if both feet have been blocked). It is better to have patients wait to leave the office until the blocks have started to wear off. Post-procedure foot soreness is uncommon.
When clinicians use Botox for hyperhidrosis, the onset of effects usually occurs in two to four days with a peak effect in about two weeks. Significant effects then last between five and 15 months. Allergan claims that significant effects last about 200 days.15
In our practice, patients have repeat injections about once a year. Significant reduction in sweating occurs in almost all patients. However, if one uses conservative amounts of toxin, one can perform a follow-up treatment — using a smaller amount of toxin — after about two weeks (but less than four weeks, which would be a free treatment). Try to avoid the need for “touch-up” treatment because of the likely need for another nerve block. (For some caveats on dosing, see “Pertinent Pointers On Ensuring The Correct Dosage” at right.)
One can treat plantar hyperhidrosis effectively with either sympathectomy or botulinum toxin. However, sympathectomy can be complicated with compensatory hyperhidrosis in another body part. This is much less common with BTX-A injections. However, a somewhat surprising observation in one paper is that many patients afflicted with both palmar and plantar hyperhidrosis and treated with palmar BTX-A had a worsening in their plantar hyperhidrosis.24
Topical use of botulinum toxin with nanotechnology is on the horizon. Preliminary studies involving the cosmetic use of botulinum toxin have shown similar efficacy to injections.26,32 If this approach proves to be efficacious, this will eliminate the painful injections into the palms and soles of the feet, the need for a nerve block and the need for skill in performing the procedure.
Then many more licensed healthcare professionals will be “qualified” to treat hyperhidrosis with botulinum toxin and the cost will probably be less. There will also be marked increase in competition. The good comes with the bad and it is not something you should sweat about.
Dr. Levine practices at Institute Beauté in New York City and is board-certified in podiatric surgery. She is the co-chair of the International Aesthetic Foot Society.
Dr. Lautin practices at Institute Beauté in New York City. He is the co-chair of the International Aesthetic Foot Society.