Is phentermine like caffeine? and Does ibuprofen affect phentermine?

Is there a difference between phentermine and caffeine?

No, not at all. There is no caffeine in phentermine. Phentermine's main ingredient, phentermine hydrochloride, is responsible for the apparent boost in energy. Ibuprofen and phentermine have no known interactions. This isn't to say there aren't any interactions. Always seek medical advice from a qualified professional.