Q:  Symbyax & Treating Bipolar Disorder

Hi Dr. Phelps, 

I noticed that you don't list Symbyax on your list of mood stabilizers on your website, yet I've heard that psychiatrists are prescribing it more and more for bipolar. I'm curious what your opinion of this drug is. . . . 

Thanks,
Piper


Hello Piper --

Fair question.  As you have learned, Symbyax is a combination of olanzapine (Zyprexa) and fluoxetine (formerly Prozac). And you probably also have learned that olanzapine is a "mood stabilizer" (in a relatively loose use of the term; technically it is a "second-generation antipsychotic"); whereas fluoxetine is an antidepressant. 

So in Symbyax we do not really have a separate or new medication; we have a combination of two medications which have been studied independently for years.  

Olanzapine is really a remarkable medication.  It is extremely effective against manic-side symptoms and also effective against depression symptoms, although I'm not as confident in its strength against depression.  Therefore, it combining it with an antidepressant is rather appealing.  When combined, the two medications together were more effective against bipolar depression symptoms then olanzapine alone. 

Since depression is the predominant problem in bipolar disorder, you might wonder why we don't just use Symbyax all the time.  That too is a fair question.  For me, I'm generally trying to keep antidepressants out of the picture, so I have little incentive to have one in there -- let alone one that is stuck together with the olanzapine.  Moreover, I generally try not to use olanzapine either, because it is much more likely to cause weight gain than other medications which are somewhat similar, principally quetiapine (Seroquel). Quetiapine has strong antidepressant effects (it has never been studied head-to-head versus olanzapine, or Symbyax, for bipolar depression; that would be interesting). 

Therefore I use Symbyax only extremely rarely, one I've tried everything else.  One of my college thinks that it is somehow kind of magical, better than just combining olanzapine and fluoxetine at the doses that we use routinely. Those kinds of judgments are extremely subject to personal experience with a lucky sample, so I do not trust them much, but I do not entirely ignore them either, particularly when they come from a colleague who has plenty of opportunity to practice with this idea. 

I hope that addresses your question.  Good luck with your research --

Dr. Phelps




Published July, 2008