It probably depends entirely on why you are getting it. Some things, like
withdrawal of hormones during menopause, can be treated, others might not be so treatable. You should check with the appropriate doctor based on why you're getting the problem.
Here is from Wikipedia:
Causes of formication include normal states such as onset of menopause (i.e. hormone withdrawal). Other causes are medical conditions such as diabetic neuropathy, skin cancer, syphilis, Lyme disease or herpes zoster.