What causes the crawling feeling in your head?

Formication. Formication is the sense that something is crawling on your skin. It has many possible causes: menopause, Morgellon's Disease, allergies, skin cancer, syphilis, diabetic neuropathy, Lyme Disease, Herpes Zoster, pesticide exposure, mercury poisoning, alcohol withdrawal, medication /drug use such as: amphetamines, cocaine, Adderall or Ritalin (methylphenidate).
Formication. Possible causes are High fever, Herpes zoster, illicit substances such as Meth, Morgellon's disease, Menopause, Allergies, Heavy metal poisoning such as Mercury, Diabetic neuropathy, Skin cancer, Lyme disease, Withdrawal from alcohol or Opiates.