Clamping is intended to permit the reversal of the procedure. ETS is generally considered a "safe, reproducible, and effective procedure and most patients are satisfied with the results of the surgery". Satisfaction rates above 80% have been reported, and are higher for children. The procedure brings relief from excessive hand sweating in about 85–95% of patients. ETS may be helpful in treating axillary hyperhidrosis, facial blushing and facial sweating, but failure rates in patients with facial blushing and/or excessive facial sweating are higher and such patients may be more likely to experience unwanted side effects.ETS side-effects have been described as ranging from trivial to devastating. The most common side-effect of ETS is compensatory sweating (sweating in different areas than prior to the surgery). Major problems with compensatory sweating are seen in 20–80% of patients undergoing the surgery. Most people find the compensatory sweating to be tolerable while 1–51% claim that their quality of life decreased as a result of compensatory sweating." Total body perspiration in response to heat has been reported to increase after sympathectomy. The original sweating problem may recur due to nerve regeneration, sometimes as early as 6 months after the procedure.Other possible side-effects include Horners Syndrome (about 1%), gustatory sweating (less than 25%) and excessive dryness of the palms (sandpaper hands).
Both the International Hyperhidrosis Society and the Canadian Hyperhidrosis Advisory Committee have published treatment guidelines for focal hyperhidrosis that are said to be evidence-based. Prescription medications called anticholinergics, often taken by mouth, are sometimes used in the treatment of both generalized and focal hyperhidrosis. Anticholinergics used for hyperhidrosis include propantheline, glycopyrronium bromide or glycopyrrolate, oxybutynin, methantheline, and benzatropine. Use of these drugs can be limited, however, by side-effects, including dry mouth, urinary retention, constipation, and visual disturbances such as mydriasis (dilation of the pupils) and cycloplegia. For people who find their hyperhidrosis is made worse by anxiety-provoking situations (public speaking, stage performances, special events such as weddings, etc. ), taking an anticholinergic medicine before the event may be helpful.Several anticholinergic drugs can reduce hyperhidrosis. Oxybutynin (brand name Ditropan) is one that has shown promise,  although it can have side-effects, such as drowsiness, visual symptoms and dryness of the mouth and other mucous membranes. Glycopyrrolate is another drug sometimes used. It is said to be nearly as effective as oxybutynin, but has similar side-effects. In 2018, the U.S. Food and Drug Administration (FDA) approved a glycopyrronium bromide-containing disposable cloth (brand name Qbrexza) for the treatment of primary axillary hyperhidrosis.For peripheral hyperhidrosis, some chronic patients have found relief by simply ingesting crushed ice water. Ice water helps to cool excessive body heat during its transport through the blood vessels to the extremities, effectively lowering overall body temperature to normal levels within ten to thirty minutes.