Caustic pencil

The silver and potassium nitrates in caustic pencils is in a dried, solid form at the tip of a wooden or plastic stick.

Silver nitrate sticks are often used for minor hemostasis where patients are not under general anesthesia, and where electrocautery would be painful and inconvenient.

The stick is rolled on the affected mucous membrane or visible blood vessel in the nares (nostril) where the chemical cauterization stops the minor bleeding.

This is especially important, as it is often used in the nose where accidental aerosolization can occur, splattering the clinician or other parts of the patient and causing unintentional burns.

Accidental application to unintended tissue is treated with copious water irrigation, and saline solution will inactivate the chemical reaction.