It is illegal to buy or sell controlled substance online.
Controlled substance is listed here:
Federal law prohibits buying controlled substances such as narcotic pain relievers (e.g., OxyContin®, Vicodin®), sedatives (e.g., Valium®, Xanax®, Ambien®), stimulants (e.g., phentermine, phendimetrazine, Adderall®, Ritalin®) and anabolic steroids (e.g., Winstrol®, Equipoise®) without a valid prescription from your doctor. This means there must be a real doctor-patient relationship, which by most state laws requires a physical examination. Prescriptions written by “cyber doctors” relying on online questionnaires are not legitimate under the law.
Buying controlled substances online without a valid prescription may be punishable by imprisonment under Federal law. Often drugs ordered from rogue websites come from foreign countries. It is a felony to import drugs into the United States and ship to a non-DEA registrant.