"Sympathectomy is a technique about which we have limited knowledge, applied to disorders about which we have little understanding." Associate Professor Robert Boas, Faculty of Pain Medicine of the Australasian College of Anaesthetists and the Royal College of Anaesthetists

http://www.pfizer.no/templates/Page____886.aspx

Postsympathectomy pain of such severity that parenteral narcotics afforded no relief

Fifty-six consecutive patients who subsequently underwent ninety-six lumbar sympathectomies were studied prospectively with regard to the development of postoperative pain. Pain after operation was observed in thirty-four extremities by twenty-five of the patients (35 per cent). It began abruptly an average of twelve days after operation and was often accentuated nocturnally. The pain was almost always described as a deep, dull ache and persisted two to three weeks before spontaneously remitting. Postsympathectomy pain of such severity that parenteral narcotics afforded no relief developed in two of these fifty-six patients and in nine additional patients. Treatment with carbamazepine produced dramatic reduction in the intensity of pain in seven of these nine patients within twenty-four hours after the institution of therapy. Two patients were given intravenous diphenylhydantoin and both experienced immediate relief of pain. The mechanisms of the syndrome and of the action of these drugs are uncertain.

A randomized placebo-controlled trial of oxybutynin for the initial treatment of palmar and axillary hyperhidrosis


Palmar and axillary hyperhidrosis improved in >70% of the patients, and 47.8% of those presented great improvement. Plantar hyperhidrosis improved in >90% of the patients. Most patients (65.2%) showed improvements in their quality of life. The side effects were minor, with dry mouth being the most frequent (47.8%).

Journal of Vascular SurgeryVolume 55, Issue 6June 2012Pages 1696-1700

Long-term efficiency? 40% affirmed they would ask for the operation if it were to be redone, 53% recurrence

At an average 12 years after surgery, 47% of patients were satisfied with the treatment results, 40% were disappointed. 
53% complaining about a decent to moderate recurrence of hand sweating and compensatory and gustatory sweating were observed in 9 (60%) and 5 (33%) patients, respectively. 
Interact CardioVasc Thorac Surg(1): 54-57.

Only 56% would recommend thoracoscopic sympathectomy to others with hyperhydrosis

http://www.ncbi.nlm.nih.gov/pubmed/21539945