Hair Loss — [very] Rare Causes

Thyroid Disease: Other Sx invariably present
  • Can order a simple TSH (very low yield)
Vitamin A Toxicity (not so rare)
  • Skin turns orange-color
  • History of excessive carrot juice or high-dose vitamins

Selenium toxicity:  Only among OTC vitamin faddists

Thallium Poisoning:
  • Nausea & vomiting occur right away
  • Rapidly progressive hair loss begins at 2-3 weeks
  • Hair loss accompanied by painful peripheral neuropathy
  • Call poison control if suspicious
Zinc Deficiency:
  • Consider in the debilitated, or elderly without adequate food access
  • Consider in persons with cirrhosis or chronic pancreatitis
  • Can be exacerbated by diuretics and ACE-Inhibitors
  • Diagnose by empiric supplementation (serum zinc testing unreliable)