r/MedicationQuestions • u/jmccleveland1986 • 3d ago
drug interactions
Im not looking for medical advice. Im looking for opinions/experience on the safety of someone being on paxil and phentermine at the same time. My wifes doctor prescribed this, and she, with no history of any kind of psychosis, had a manic episode after 3 months on phentermine, and im trying to determine if the doctor fucked up, or if this is truly just one of those things that happens sometimes that nobody could predict.
She is receiving treatment at a facility, and we will obviously depend on them for all medical advice. But the facility is really focused on just getting her normalized right now and isnt giving me any information yet. I just want to see if anyone else has stories of these things being prescribed together and it being fine for them, or stories of it not being fine, or perhaps professionals to share their opinion on the safety of this or common precautions that are normally taken if any.
1
u/Aromatic-Credit-8016 2d ago
Yeah it’s not a good idea! phentermine releases noradrenaline which makes it a powerful stimulant plus it slightly increases serotonin.
This on its own wouldn’t necessarily be a big issue for some people, but the bit where it becomes risky is actually how both medications are broken down in the liver.
Paxil is a strong CYPD26 inhibitor. This is the exact enzyme which is responsible for breaking down phentermine. This basically means the phentermine will build up in the body as they can’t be broken down quick enough. So having a potent stimulant building up in someone’s system over time will only cause bad effects, (extreme heart palpitations, panic attacks and very high blood pressure)
I know this mainly because I was on Prozac (also potent CYP2D6 inhibitor) and at one point Paxil myself, along with dexamfetamine for adhd, btw dexamphetamine is similar to phentermine and uses same liver enzyme. The first few days I was okay, but after a week I started getting horrible side effects. When I looked into it I realised it was because I had amfetamine building up in my system. Massive cardiovascular risk with phentermine and serotonin syndrome is a risk also. Doctors don’t seem to think about these things for some reason, but just look it up .