Primary hyperhidrosis usually first appears during puberty or early adolescence and continues throughout adulthood. Secondary hyperhidrosis may develop at any time in response to a separate medical condition (e.g., hyperthyroidism) or other factors (e.g., stress). Visible signs of hyperhidrosis are often obvious and may include underarm stains, dripping palms or wet clothing.

The most commonly affected areas are the armpits, palms of the hands and soles of the feet. However, hyperhidrosis can impact any part of the skin’s surface except for the lips, external ear canal and sex organs, which do not have the capacity to produce sweat.

Individuals with underarm hyperhidrosis may experience the following symptoms:

• Softening, whitening or cracking of the skin from persistent wetness
  
  
• Small, itchy rashes caused by sweat trapped under folds of skin (prickly heat)
  
  
• Inflammation or irritation of the affected area
  
  
• A stinking odor may emanate from the affected area (bromhidrosis) due to overgrowths of sweat–related bacteria

It is recommended that individuals who experience a marked increase in sweating or any other symptoms of hyperhidrosis consult their physician.