AS the popular weight loss supplements containing ephedrine make their way off of store shelves, the people who bought them have found another fat-burning substitute. Some ephedrine manufacturers have already started making ephedrine-free products that are supposed to produce the same energetic results. But researchers still don`t know if the side effects are the same. "It`s not as intense. Most people are finding that they have to take a little bit more of the ephedrine free product to get the same effect," said Russell Hill, Fitness Tech Equipment and Nutrition. Instead of ephedra, those supplements use a chemical called bitter orange to produce the same results: more energy and a lower appetite. "The drug found in bitter orange is called sinephrine, chemically pharmacologically similar to ephedrine, like the first cousing to ephedrine," said Bill Gurley, Ph.D., UAMS College of Pharmacy. Gurley says the effects of these supplements could be the same as those containing ephedra. But it`s just too early to tell, since little research has been done on them at this point. "Those ephedra free prodcuts may not be as problematic but do show some potential for adverse toxicological effects," Gurley said. Russell Hill says they`re definitely safer. Gurley stresses that only few people will suffer heart attack, stroke, or seizure caused by ephedrine supplements, but anyone taking them is at a greater risk.