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A member asked:

I have been taking phentermine 37.5 mg and am almost done with my 3 month prescription. can i take fastin otc when i am done as a maintenance drug?

A doctor has provided 1 answer

At least 3 days: While Fastin OTC is not the same chemical as phenteramine, both can affect the heart. Make sure your heart health is ok before starting a new diet med.

Answered 12/3/2016

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