<Li> Cantharidin is an extract of the blister beetle that causes epidermal necrosis and blistering . It is used to treat warts . </Li> <P> Frequent nose bleeds are most likely caused by an exposed blood vessel in the nose, usually one in Kiesselbach's plexus . </P> <P> Even if the nose is not bleeding at the time, a physician may cauterize it to prevent future bleeding . Cauterization methods include burning the affected area with acid, hot metal, or lasers . Such a procedure is naturally quite painful . Sometimes, a physician uses liquid nitrogen as a less painful alternative, though it is less effective . A physician may apply cocaine in the few countries that allow it for medical use . Cocaine is the only local anesthetic that also produces vasoconstriction, making it ideal for controlling nosebleeds . </P> <P> More modern treatment applies silver nitrate after a local anesthetic . The procedure is generally painless, but after the anesthetic wears off, there may be pain for several days, and the nose may run for up to a week after this treatment . </P>

How hot does metal need to be to cauterize a wound