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Date of last update: 9/4/2017.

Forum Name: Nutrition & Diet

Question: Diet pills (phentermine, bontril)

sonshines33 - Tue Jan 31, 2006 6:23 pm

I am a 36 yr. old female who's currently taking Zoloft and have been taking it for about 7 yrs. I would really like to lose some weight and have found that phentermine worked very well for me in the past but I believe I have become immune to it because it no longer works for me. My question is, if I take another prescribed diet pill such as bontril, will I be immune to it as well, or since it is a different pill will it work for me? I don't want to invest the money in it if it's not going to do it's job. It had been almost 9months between the last time I took the phentermine and I can't believe within that amount of time that I would become immune to it. I guess I took it for to long a period of time. Anyway, should I go with the bontril, if not can you suggest another diet pill? Thanks for your time.
Theresa Jones, RN - Wed Jul 26, 2006 2:02 pm

Hi sonshines33,
The medications that you are inquiring about would be inadvisable to be used in conjunction. Please consult your physician regarding this matter and also inquire about a nutrition and exercise plan. The following information is provided by the drug interaction checker on Click here!

"Drug-Drug Interactions
phendimetrazine and Sertraline (major Drug-Drug)
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.
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".
Theresa Jones, RN

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