Fear of Fear
Fear of experiencing fear itself is called phobophobia. It can involve anxiety about a possible panic episode or the symptoms of another phobia, which may reinforce avoidance.
However, the claim that it is “one of the hardest phobias to cure” is not supported by reliable clinical evidence. Medical sources describe phobophobia as a rare form of specific phobia, but do not rank phobias by treatment difficulty. Effective approaches, including cognitive behavioral therapy and gradual exposure, are available for specific phobias generally.