There isn’t any known cause. It is manifested in circumscribed bilaterally symmetrical areas and extremities.

Primary or idiopathic hyperhidrosis produces excessive sweating frequently located in the palms, the axillae, the face and/or the feet. Eventually it may affect the trunk and the scalp with different combinations of severity and locations. Excessive sweating is very embarrassing and uncomfortable to those who have it. The social, professional and especially the emotional damages is great. The most consistent complaints are embarrassment when shaking hands and difficulties in writing and drawing.

The clinical features of Primary Hyperhidrosis are:

• It often begins in the first years of life, it worsens during puberty and it persists for one’s whole life.
• There is no difference in frequency between males and females, however axillar hyperhidrosis shows up a little more often in females than in males.
• It occurs in all races, especially Jews and Asians.
• It mainly affects the palms, the axillae, the face and the feet, with different combinations of severity and locations.
• Sweat glands are normal in patients with hyperhidrosis.
• There is little difference of intensity between summer and winter.
• The sweating is not usually aggravated by exercise.
• The most important stimuli for sweating are emotional, thermal and gustatory.
• Emotional factors cause much more severe sweating than the others.
• Sweating is usually absent when the patient is completely relaxed, as during sleep.
• Patients usually have a family history of hyperhidrosis; this finding suggests a genetic factor in the pathogenesis of this disorder.