Eccrine sweat glands are controlled by the sympathetic nervous system but use cholinergic (acetylcholine) signaling. In primary hyperhidrosis, there is sympathetic overactivity and central dysregulation, causing normal stimuli to produce disproportionately high sweat output—without an increased number of glands. 

Variations

• Focal (axillae, palms, soles, face) vs generalized.

• Primary (idiopathic, usually focal and starting in youth) vs secondary (due to medications or systemic disease). 

Severity & treatment approach

• Mild: topical antiperspirants, lifestyle measures.

• Moderate focal: botulinum toxin injections are widely used and evidence-based to block acetylcholine at the gland level.

• Severe or generalized: systemic medications or surgical options may be considered by specialists; crucial to exclude secondary causes first.