DO NOT TAKE PHEN WITH SSRI ANTIDEPRESSANTS

**zippysgoddess** · 06-14-2005, 08:34 PM

Just found this out today when the docs office called in regards to my DH's inquiry and said he can't take it with his paxil.

It can cause Seratogenic effects which can be fatal.

Here's the info from an interaction checker:

You have searched for drug interactions between the following drugs: Paxil,phentermine

Please note: only generic drug names are displayed.

phentermine and paroxetine (major Drug-Drug)
Description:

GENERALLY AVOID:
Several case reports suggest that patients treated with serotonin reuptake inhibitors (SRIs) may exhibit an increased sensitivity to sympathomimetic agents. The mechanism of interaction is unclear. The reaction has been reported when fluoxetine was used concomitantly with phentermine, amphetamine, or phenylpropanolamine. Additionally, some sympathomimetic agents (e.g., amphetamines) may possess serotonergic activity and should generally not be administered with SRIs because of the additive risk of serotonin syndrome, which is a rare but serious and potentially fatal condition thought to result from hyperstimulation of brainstem 5-HT1A receptors. The interaction occurred in a patient treated with dexamphetamine approximately 2 weeks after the addition of venlafaxine. The medications were discontinued and the patient was given cyproheptadine for suspected serotonin syndrome, whereupon symptoms promptly resolved. A second episode occurred when dexamphetamine was subsequently resumed and citalopram added. The patient improved following cessation of citalopram on his own, and residual symptoms were successfully treated with cyproheptadine.

MANAGEMENT:
In general, amphetamines should not be combined with serotonin reuptake inhibitors. Close monitoring for enhanced sympathomimetic effects is recommended if these agents must be used together. Patients should also be monitored for signs and symptoms of excessive serotonergic activity such as CNS irritability, altered consciousness, confusion, myoclonus, ataxia, abdominal cramping, hyperpyrexia, shivering, pupillary dilation, diaphoresis, hypertension, and tachycardia.
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**NeedtoLose** · 06-14-2005, 09:57 PM

I am on an SSRI and my doctor gave me Phentermine. What should I do?

Your Results
The interactive effects of —

Effexor XR + phentermine

are as follows:

Major Interaction -- Drug-Drug
venlafaxine and phentermine

GENERALLY AVOID: Several case reports suggest that patients treated with serotonin reuptake inhibitors (SRIs) may exhibit an increased sensitivity to sympathomimetic agents. The mechanism of interaction is unclear. The reaction has been reported when fluoxetine was used concomitantly with phentermine, amphetamine, or phenylpropanolamine. Additionally, some sympathomimetic agents (e.g., amphetamines) may possess serotonergic activity and should generally not be administered with SRIs because of the additive risk of serotonin syndrome, which is a rare but serious and potentially fatal condition thought to result from hyperstimulation of brainstem 5-HT1A receptors. The interaction occurred in a patient treated with dexamphetamine approximately 2 weeks after the addition of venlafaxine. The medications were discontinued and the patient was given cyproheptadine for suspected serotonin syndrome, whereupon symptoms promptly resolved. A second episode occurred when dexamphetamine was subsequently resumed and citalopram added. The patient improved following cessation of citalopram on his own, and residual symptoms were successfully treated with cyproheptadine.

MANAGEMENT: In general, amphetamines should not be combined with serotonin reuptake inhibitors. Close monitoring for enhanced sympathomimetic effects is recommended if these agents must be used together. Patients should also be monitored for signs and symptoms of excessive serotonergic activity such as CNS irritability, altered consciousness, confusion, myoclonus, ataxia, abdominal cramping, hyperpyrexia, shivering, pupillary dilation, diaphoresis, hypertension, and tachycardia.

**zippysgoddess** · 06-14-2005, 10:02 PM

I would say to make sure your doctor is aware of this possibility as some of them aren't. Our pharmacy actually caught it first.

They do say if you use them together you should be closely monitored. Watch yourself and if you notice any strange, or unusual symptoms or bodily changes, contact your doctor or go to an emergency room immediately!

**NeedtoLose** · 06-14-2005, 10:05 PM

I take the Phentermine in the morning and effexor at night before bed. Do you think that makes a difference? Should I call my pharmacist and ask them about taking them?

**zippysgoddess** · 06-14-2005, 10:11 PM

It couldn't hurt to call and double check, better safe than sorry. They won't let my DH take it at all with his Paxil.

**NeedtoLose** · 06-14-2005, 10:22 PM

I called the Pharmacist. Effexor is different from a SSRI because it works in 2 parts of the brain. It works with Serotonin and another part of the brain. Therefore it is not as bad as taking it with a SSRI, but I do have to be monitored.

I have to go to the doctor monthly to have my heartrate tested. He already told me I would have to do that, I just did not know that was the reason why.

**zippysgoddess** · 06-14-2005, 11:17 PM

Great, I am glad you called and found out for sure. It sounds like Effexor is more like Cymbalta, it also works on more than just Seratonin.

**NeedtoLose** · 06-15-2005, 12:51 AM

Quote:

Originally Posted by zippysgoddess

Great, I am glad you called and found out for sure. It sounds like Effexor is more like Cymbalta, it also works on more than just Seratonin.

Thanks for the info though. It is still nice to know that I need to be more aware of my symptoms.