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A member asked:

How many days should taking my ritilan after taking phentermine? (wait how long to start my ritilan if i've been taking phentermine?)

A doctor has provided 1 answer
Dr. Donald Haupt answered

Specializes in Psychiatry

2 days or more: Phentermine has a half life of 20 hours, so it is basically not having much effect after a day or two. Its completely gone in 5 days. Phentermine is a stimulant usually used in weight loss. Since Ritalin (methylphenidate) is a stimulant too, you should not be on both at the same time, nor is it good to alternate them.

Answered 9/28/2016

5.1k views

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