How long is it safe to take phenteine to lose weight? an is it safe to take while taking syntthroid?

Yes and no!: Fda approved, it can have side-effects: tachycardia, arrthymias, and an increase in blood pressure. The problem with phenetermine is that it usually will deliver a 10-15 lb weight loss and it's effects diminish and do not continue. It works by both suppresing appetite and increasing metabolism. If your thyroid dose is correct, shouldn't pose an issue. If high, serious problems could arise! diet!

3 months if Md ok: I typically do not prescribe Phentermine for longer than 3 months. Before starting its important to have your doctor check your heart rate, blood pressure, and make sure you do not have an overactive thyroid. Finally there are some antidepressant meds that interact badly with phentermine.