Hi,
I'm sorry to hear you've been having some problems with your health while on phentermine. Phentermine has many side effects, such as increased blood pressure, trouble sleeping, dry mouth,
constipation, and nervousness.
From my experience and what I've read, phentermine should not cause fatigue or
shortness of breath.
You may want to see your doctor about these new symptoms, he/she may want to check out your heart because sometimes patients with a lot of extra weight can have problems with breathing when they are asleep. (called
obesity hypoventilation syndrome).
This eventually damages the heart (causing pulmonary
hypertension).
As for the stomach problems, I'm not sure what could be causing that, except that constipation is a known side effect of phentermine, and what you are feeling could be that your intestines are full of stool.
I would try taking a laxative or
stool softener like docusate or Bisacodyl to see if that helps.
Hope I have answered your query. Let me know if I can assist you further.
Regards,
Dr Aaron Branch, General & Family Physician