I'm taking plaqeunil, mobic, (meloxicam) prednisone for rheumatoid arthritis. can i use phentermine for weight loss while on these other medications?

You: Can, but why are you still on Prednisone causes weight gain, while there are better combinations. Watch for heart rate increases, blood pressure increases.

Weight medications: The easy answer is "yes." however 1) the weight gain tendency caused (primarily) by Prednisone will continue, so consider finding an effective regimen for your RA and pain that doesn't cause weight gain. 2) Phentermine generally only works well for a short period of time. Most people who use it find that it wears off after several weeks or months. There may be better weight options besides phent.