Shown: posts 1 to 4 of 4. This is the beginning of the thread.
Posted by Rick on March 23, 2000, at 14:34:10
Does it seem feasible that Serzone could induce a transient increase in blood pressure?
I have a friend who developed very high baseline blood pressure a few years ago, but has been keeping it under pretty good control lately with five (yes, five) different BP meds. Incidentally, this includes the Calcium Channel Blocker Procardia Extended-Release (nifedipine), which I understand is metabolized by one of the enzymes that is powerfully inhibited by Serzone(nefazodone). He typically has normal to moderately high readings first thing in the morning (anywhere from 120/80 to 150/105, with 140/90 being typical), and then normal-to borderline-high readings the rest of the day (115/75 - 130/85).
Now, he had been on Serzone about three weeks (for general anxiety and possible mild depression) with no change in BP, except perhaps a little morning lowering(no other side effects except a little dry mouth). But about nine days ago he was increased from 300mg/day to 400, and about five days ago suddenly started getting morning readings as high as 170/125 and daytime readings up to 155/105. This lasted about three days, and then for the last few days he has been getting really good readings, e.g. around 120/80 -- even first thing in the morning.
While his BP seems stress reactive, the period where it started shooting up was NOT a particularly stressful one, he says.
Bottom line question: Is it possible Serzone drove a transient increase in BP? If so, is it likely to happen again?
Thanks in advance for any input,
Rick
Posted by Cam W. on March 23, 2000, at 20:42:02
In reply to Transient Blood Pressure Increase due to Serzone? , posted by Rick on March 23, 2000, at 14:34:10
Rick - Yes, Serzone does inhibit CYP-3A4 very potently and Nifedipine is metabolized by this enzyme ststem, therefore one would expect elevated Nifedipine blood levels. BUT, things are never this easy. Even though nifedipine is mainly hydroxlated by CYP-3A4 the genetic make up of your friend MAY offset the inhibition (ie his liver may produce plenty of enzyme to keep Nifedipine metabolism at normal levels - but this is unlikely). One would expect the increased blood levels of Procardia to cause hypotension.Does he get his Serzone and Procardia prescribed by the same doctor? If different doctors are prescribing, do they know of each other's existence?
Does he use the same pharmacy for all his medications? The computer should have flagged this interaction.
Serzone frequently causes hypotension, but infrequently can cause hypertension. The Serzone MAY have contributed to the increase in blood pressure.
My conclusions - I don't know for sure, but the above are educated guesses.
Hope this helps - Cam W.
Posted by Rick on March 23, 2000, at 22:52:08
In reply to Re: Transient Blood Pressure Increase due to Serzone? , posted by Cam W. on March 23, 2000, at 20:42:02
Thanks for the thoughts, Cam. My friend sees a well-respected hypertension specialist strictly for blood pressure, and a GP for most other things. They are indeed aware of each other. I would assume each has a full list of meds he uses, although I'm not sure; I'll ask. I do know that the hypertension specialist is not yet aware that the GP prescribed Serzone. The BP meds come from a mail-order maintenance-prescription service, while the Serzone comes from a regular pharmacy. Does flagging an interaction necessarily mean "don't take these together"?
One other question: A few years ago, at age 45, he had what was apparently a TIA one morning before work (fleeting blindness in one eye). He was taking BP meds at the time, but a much less extensive regimen, and was not monitoring closely. Extensive tests a few weeks later showed no sign of physical risk factors or possible cause other than high BP. Now, I notice the Serzone monograph says to use with caution in people who have cardiovascular disorders including stroke. Would this suggest that Serzone should not be used by someone who had a mild TIA of unknown origin?
Thanks,
Rick
Posted by Cam W. on March 23, 2000, at 23:08:00
In reply to Re: Transient Blood Pressure Increase due to Serzone? , posted by Rick on March 23, 2000, at 22:52:08
Rick - Flagging a prescription means (on my system anyway) that a warning comes up telling you of a potential drug interaction, it's seriousness and references.Never assume that doctors share notes; most don't. The pharmacy should take the initiative to contact each doctor with changes in drug regimens (another beef I have with mail-order pharmacies).
He should tell his specialist about the Serzone. I'll bet the doc pales.
I am not sure about the TIA thing, but I would use Serzone with caution in someone who has definitely has had one (doesn't seem definitive that he did).
Please have your friend contact is heart doc, I believe that it is important he know of the Serzone use. - Cam W.
This is the end of the thread.
Psycho-Babble Medication | Extras | FAQ
Dr. Bob is Robert Hsiung, MD,
bob@dr-bob.org
Script revised: February 4, 2008
URL: http://www.dr-bob.org/cgi-bin/pb/mget.pl
Copyright 2006-17 Robert Hsiung.
Owned and operated by Dr. Bob LLC and not the University of Chicago.