KOH

Medical abbreviation · Dermatology

KOH
Stands forPotassium hydroxide (preparation)
CategoriesMedical

KOH stands for Potassium hydroxide (preparation), a dermatology abbreviation.

Quick office test in which skin scrapings, nail clippings or hair are placed on a slide with potassium hydroxide, which dissolves keratin and reveals fungal hyphae or yeast under the microscope. It confirms tinea, candidiasis and tinea versicolor.

Example: KOH of scaly groin rash positive for branching hyphae; start terbinafine cream.

Usage notes

KOH is the chemical formula for potassium hydroxide (K for potassium). Tinea versicolor shows a characteristic "spaghetti and meatballs" pattern of hyphae and yeast. In gynecology, adding KOH to vaginal discharge releases a fishy odor (the whiff test) in bacterial vaginosis. Results are available in minutes.

More dermatology abbreviations

  • EM – Erythema migrans
  • GA – Granuloma annulare
  • HA – Hyaluronic acid (filler)
  • HS – Hidradenitis suppurativa
  • ICD – Irritant contact dermatitis
  • IPL – Intense pulsed light
  • KP – Keratosis pilaris
  • LP – Lichen planus
  • LS – Lichen sclerosus
  • MCC – Merkel cell carcinoma
  • MIS – Melanoma in situ
  • MM – Malignant melanoma

See all 52 dermatology abbreviations →

This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.