TAMPA, Fla. (WFLA) — The Food and Drug Administration and the Drug Enforcement Administration (DEA) have issued warning letters to two websites for illegally selling Schedule II stimulants, such as Adderall, without prescriptions, the FDA said Tuesday.

The warning letters were issued to Kubapharm.com and Premiumlightssupplier.com on March 30. The companies have 15 business days to respond to the warning.

Adderall is a prescription drug used to treat attention deficit hyperactivity disorder (ADHD) and narcolepsy. The drug is a combination of amphetamine and dextroamphetamine, two central nervous stimulants that improve attention span and focus.

Adderall was approved by the FDA in 1996. 

The FDA says consumers who buy prescription drugs from unsafe online pharmacies may put their health at risk because the products may be counterfeit, contaminated, expired, or otherwise harmful. 

“This action underscores the FDA’s commitment to use all available regulatory and compliance tools to stop online businesses illegally selling potentially harmful drug products to consumers,” said FDA Commissioner Robert M. Califf, M.D. “The illegal sale of prescription drug stimulants online puts Americans at risk and contributes to potential abuse, misuse, and overdose.

“These particular types of online pharmacies also undermine our efforts to help consumers safely purchase legitimate prescription medicines over the internet,” he said. “FDA will continue partnering with DEA in an effort to safeguard public health and protect consumers who need access to these important medicines.”