That's a load of crap, ever heard of mithridatism? Like every other stimulant, people build a tolerance to ephedrine and eventually it stops being effective at a certain dose.
Either way... the side effects of ephedrine overuse are mostly related to its effects as a blood pressure elevator and cardiac stimulant. Increased risk of stroke, aneurysms, etc, if your blood pressure runs abnormally high. It's also a thermogenic - raises body temperature - as well as an appetite supressant, so you have to make it a point to eat properly.
Realistically, if your blood pressure is within normal limits, (which it may well be - I imagine after 9 years of eph use you must have a solid tolerance - but it may not, so get it checked!) and you seem physically healthy otherwise you probably don't have too much to worry about. Well, until you stop taking it.
Realistically if you take large doses of any amphetamine-type stimulant, and then stop, you'll probably sleep for 72 hours and feel crappy for a week. Probably.
TL;DR: Get a physical and check your blood pressure. If everything's ok... Play it by ear.
