After weeks of individual reports of frustration with getting Adderall prescriptions filled, the Food and Drug Administration confirmed Wednesday a nationwide shortage of the immediate release formulation of amphetamine mixed salts, commonly referred to by the brand name Adderall.Some individuals already knew there was a problem having reported going weeks without medication and calling multiple pharmacies to fill prescriptions.Teva, the largest maker of generic Adderall in the U.S., told ABC News "the supply that we are manufacturing/distributing right now is on pace to be consistent – or greater than – our supply at this time last year by the end of this year.While another supplier of the drug, Sandoz Pharmaceuticals (a division of Novartis) told ABC News there is no "shortage" of Sandoz amphetamine (generic Adderall) in the market at this time and the company is meeting all current customer orders.A "classroom of kids who have had to quit their meds cold turkey because they can't get them – we've got some issues going on and brewing here," Spires, in Kentucky, said."