It can be a side effect of Ritalin (methylphenidate), Adderall (dextro/levo-amphetamine) and Lunesta (
eszopiclone) and other prescription drugs or of cocaine or amphetamines. (Accordingly, it goes by the slang term "coke bugs".) Formication can also be a withdrawal symptom of weaning oneself off cocaine or amphetamine. It can also accompany alcohol withdrawal in alcoholics, along with delirium tremens.