![[dr. bob]](/dr-bob-sm.gif)
Dr. Bob is Robert Hsiung, MD,
bob@dr-bob.orgShown: posts 1 to 6 of 6. This is the beginning of the thread.
Posted by BrainDamage on May 26, 2014, at 12:41:44
Been reading some alarming things about the possible interactions with Quetiapine & Trycyclics
Would a relativivly low dose of Quetiapine, 200mg
interact with Desipramine or Nortryptaline?
Any thoughts or experiences?
Posted by tom2228 on May 26, 2014, at 13:06:49
In reply to Quetiapine + Trycyclics-Interactions?, posted by BrainDamage on May 26, 2014, at 12:41:44
No, not metabolically or anything serious, but you will have some synergy.
-For both there will be additive effects on norepineprhine since norquetiapine (active metabolite of quetiapine) is an NRI like desipramine and nortriptyline
-There will be additive sedative effects with nortriptyline (histamine), as well as extra weight gain
-There will be additive effects on 5-HT2 receptors with nortriptyline, yielding antidepressant synergy and extra weight gain (5-HT2c)
-And there might be additive effects on orthostatic hypotension, dizziness when standing as all 3 drugs block alpha-1 adrenergic receptors
Posted by BrainDamage on May 26, 2014, at 16:59:14
In reply to Re: Quetiapine + Trycyclics-Interactions?, posted by tom2228 on May 26, 2014, at 13:06:49
> No, not metabolically or anything serious, but you will have some synergy.
>
Thanks Tom
I should have mentioned that I was concerned about Cardiac side-affects
Apparently Quetiapine has some Cardiac affects
Trycyclics can cause Tachycardia ect
The Trycyclic I'm taking is called Lofepramine
And has less or an affect on the heart than most Trycyclics
I'm hoping at 200mg Quetiapine won't have much of an effect on the heart
Posted by Christ_empowered on May 26, 2014, at 17:20:20
In reply to Re: Quetiapine + Trycyclics-Interactions?, posted by BrainDamage on May 26, 2014, at 16:59:14
ugh. I wouldn't do it, personally. Low doses though, a cleaner tca...maybe not a big deal?
Could you just try a low dose of risperidone? maybe prn, even?
Posted by tom2228 on May 26, 2014, at 17:37:08
In reply to Re: Quetiapine + Trycyclics-Interactions?, posted by Christ_empowered on May 26, 2014, at 17:20:20
Lofepramine is unique among the tricyclics in that it lacks arrtyhmogenicity (the propensity to cause arrythmias), so it's probably the safest TCA cardiologically.
But the issue with quetiapine is separate and has to do with prolongation of the qTC interval, which is not that dramatic compared to other drugs. One usually only has to worry about qTC interval issues when taking multiple drugs that have that property, or two with a particularly strong effect.
I wouldn't worry about it, but if it makes you more comfortable risperidone does have less of an effect, and paliperidone (which is less sedating that risperidone) and lurasidone do not have a clinically significant effect on the qTC interval.
There's a chart on this link if you scroll down with data regarding the extent to which a variety of drugs affect that interval. Does not include TCAs but to reiterate lofepramine is okay in this regard.
And in any case all of these effects are dose-dependent. 200mg quetiapine isn't too much to worry about.
Posted by BrainDamage on May 26, 2014, at 21:59:45
In reply to Re: Quetiapine + Trycyclics-Interactions? » Christ_empowered, posted by tom2228 on May 26, 2014, at 17:37:08
> Lofepramine is unique among the tricyclics in that it lacks arrtyhmogenicity (the propensity to cause arrythmias), so it's probably the safest TCA cardiologically.
>
Wow thats a relief!
Assuming Lofepramine doesn't work, I'll have to go with Nortryptaline
Which will be a bit more of a risk, I assumeI suppose I'll just have to start with a really low dose of whatever TCA & see how it feels
Not the ideal way to monitor ones heart!
But its all I can do
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.