A counterfeit form of the drug Adderall is being sold online, the Food and Drug Administration (FDA) warned.

Adderall, prescribed for attention deficit hyperactivity disorder and narcolepsy, also is used illicitly to increase attention and get high, the Los Angeles Times reports. The drug is in short supply because of manufacturing problems, the article notes. Distributors of the fake medication are taking advantage of the shortage.

The ingredients in Adderall are dextroamphetamine saccharate, amphetamine aspartate, dextroamphetamine sulfate and amphetamine sulfate. The 30-milligram phony pills analyzed by the FDA contain the painkiller tramadol and acetaminophen.

Several spelling mistakes on the label of the fake medication make it easy to detect, according to the newspaper. The label says "NDS" instead of "NDC," "Aspartrte" instead of "Aspartate," and "Singel" instead of "Single."

According to a FDA news release, the fake Adderall tablets are round, white and do not have any type of markings, such as letters or numbers. "The counterfeit versions of Adderall should be considered as unsafe, ineffective and potentially harmful," the FDA notes. Genuine Adderall 30 milligram tablets are round, orange/peach, and notched down the middle, with "dp" marked on one side and "30" on the other side. They come in a 100-count bottle with the National Drug Code (NDC) 0555-0768-02 listed. Anyone who believes they have counterfeit Adderall should contact the FDA's Office of Criminal Investigations.