Posted by ed_uk2010 on August 20, 2014, at 14:01:18
In reply to Re: Sertraline immediately eliminated suicide thoughts, posted by Lamdage22 on August 19, 2014, at 13:51:51
>Seorquel 800
>Zyprexa 7.5
>Metformin 1500
>Venlafaxine 37.5
>
> Venlafaxine could be abandoned of course.Hi,
If you were to switch to fluvoxamine I'd suggest stopping venlafaxine anyway. Taking two SSRIs or SNRIs together is not normal practice.
It is theoretically possible to take fluvoxamine together with most interacting drugs but substantial dosage reductions will be needed.
Fluvoxamine's drug interactions are mainly due to the inhibition of two drug-metabolising liver enzymes. It leads to potent inhibition of CYP 1A2 and moderate inhibition of CYP 3A4. Olanzapine is metabolised by CYP 1A2. Quetiapine is metabolised by CYP3A4.
Evidence suggests that fluvoxamine more than doubles the blood levels of olanzapine. As a result, it is suggested to reduce the dose of olanzapine where appropriate and to consider monitoring the blood level of olanzapine. In your case, you might need to reduce olanzapine to 5mg initially. I'm not sure how your pdoc would feel about this but you can ask for nothing.
http://www.ncbi.nlm.nih.gov/pubmed/12352274
http://www.ncbi.nlm.nih.gov/pubmed/11477325
The magnitude of effect of fluvoxamine on quetiapine levels is less clear. Very potent CYP 3A4 inhibitors such as the antifungal ketoconazole can increase quetiapine levels very dramatically, requiring quetiapine to be reduced to as little as one sixth of the original dose. Fluvoxamine is not such as potent inhibitor, however. It is likely that fluvoxamine would require the quetiapine dose to be reduce to approximately half or one third of the original dose, based on evidence that fluvoxamine increases quetiapine levels by an average of 159%. In your case, this would probably mean reducing quetiapine to about 300mg per day, adjusted according to response.http://www.ncbi.nlm.nih.gov/pubmed/11477325
Metformin does not interact with fluvoxamine.
Hope this is of some help.
poster:ed_uk2010
thread:1069951
URL: http://www.dr-bob.org/babble/20140815/msgs/1070074.html