I took phentermine about 2 years ago and lost 35 pounds. I had so much energy and felt great! But i fell of the wagon and gained it all back plus some and i just recently started taking phentermine again and nothing, no energy, and im still hungry all the time.Whats so different this time than 2 years ago? I really need some help.
Why isn't the phentermine working this time?
- Asked
- 15 Feb 2011 by llm28073
- Updated
- 17 June 2018
- Topics
- obesity, weight loss, phentermine
Responses (3)
I am wondering The same thing! I took it about 2.5 years ago and lost 12 lbs the first month, total weight loss of about 47 lbs. I have been taking it again and haven't lost anything in months ! The only difference this time is I no longer smoke cigarettes. I really need to figure something out.
The same thing is happening to me Do not know the answer unless we have built up a tolerance My endoc will not let me up my dosage said for me to stop taking it since it is not working I wonder if brand name works better than generic? Does anybody have an answer to that?
I am having a similar issue with Phentermine. I took it two years ago and lost 30 pounds. I gained the weight back plus more. I started back on Phentermine a month ago and while my appetite is suppressed I do not have the extra energy. I read on another forum that all Phentermine is not the same. Some are stronger than others. I asked my pharmacist and was told they had changed distributors so I am thinking it is very possible. The pill I am getting at the Walmart Pharmacy is imprinted K 25, which according to the forum (I cannot find again) is the weakest one.

Further Information
- Phentermine Information for Consumers
- Phentermine Information for Healthcare Professionals (includes dosage details)
- Side Effects of Phentermine (detailed)
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