7th June 2025

Anhidrosis

Anhidrosis is an acquired disorder of sweating where there is a reduction in or complete loss of sweat production in response to a thermal or pharmacological stimulus.

Cause

• Idiopathic
• Peripheral alteration in eccrine gland 
• Neuropathic disease or medication that disrupt neural inputs from anterior hypothalamus to the gland

Diagnosis

• Symptoms
  • Heat intolerance
  • Fatigue
  • Drowsiness
  • Inability to concentrate in warm environments 
  • Ptosis and miosis in Horner syndrome (neuropathic anhidrosis) 
• Investigation
  • Sweat test – decreased sweat production 
  • Skin biopsy – identify sweat gland abnormality

Management

• Remove underlying cause
  • Remove offending medication (e.g., anticholinergic agents)
  • Treatment of lung carcinoma if it is causing Horner syndrome 
• Cool environments
• Frequent and gentle exfoliations