Ok so I was wondering why some opiates are stronger than others. For instance what makes oxycodone stronger than say hydrocodone? Its like opana and hydromorphone. What produces the euphoria and what makes one pill stronger in that aspect compared to another? When someone says 10 mg vicodin is equivalent to 7.5 mg of percocet , why do we even have 2 different meds? example, the doctor wants you to take 1 7.5 mg vicodin every 4-6 hours. Why not be prescribed 5mg percocet every 4-6 hours? See what I am getting at? What's mu receptors? Someone give me some cliffs on pain meds for pain relieve and recreational value. That is if someone is bored and wants to school me on a more in depth look at pharmaceutical meds. Thanks .