The NFL has moved to toughen its drug policy, adding amphetamines to the list of banned performance-enhancing drugs starting in 2007.

The league announced Tuesday that amphetamines have been elevated to the same category as steroids and other enhancers that carry stronger penalties compared to so-called recreational drugs.

This season, a first positive test for amphetamines will result in a warning and put a player into the drug program. But in 2007, players will be tested for amphetamines on a regular basis.

A first positive test will result in a four-game suspension, the same penalty now levied for positive steroids tests. A second positive test for performance-enhancing drugs will draw an eight-game ban. A third positive test carries a one-year suspension.

Some information for this report was provided by AFP, AP and Reuters.