Q:  Invega as a Treatment of BP II Mixed Mood

What is your opinion, or is there any evidence in the usage of the newly released Invega, in the treatment of BP II mixed mood?

My PDOC has recommended me to your writings, and seems to follow for the most part in your and Dr. Sachs treatment ways.

We just had tried Depakote, which helped to some degree, but weight gain, hair loss, and cognitive impairment is unfortunately forcing me to come off.

I do understand that this med is an extended release version of Risperdal, w/ perhaps less side-effects.

It is brand new, so I guess I am the guinea pig, but I wanted to get your input on your readings of this medication.

Regards,
Brian


Dear Brian --

This medication, paliperidone, is a metabolite of risperidone.  It does have an extended release mechanism, but in my understanding so far, there is no reason whatsoever to expect that we would see any more benefit from this medication than from risperidone itself.  It might perhaps have less side effects in some ways, but we have two little clinical experience with it so far to really know.

Instead, in my opinion this is more of an embarrassment then an advance: when a medication is just about to go off patent, manufacturers often come up with some fancy version for which they can obtain a new patent.  They then proclaim the advantages of the new version relative to the older version, which only months before they were advertising proudly .  In the last several years, this has become an extremely common practice.  Before Celexa went generic, the manufacturer came out with Lexapro; before Wellbutrin went generic, came Wellbutrin XL; in anticipation of a generic Ambien, we have gotten Ambien CR; and before we get a generic lamotrigine, we will also get an extended release version of that medication. You would think the manufacturers thought we were really quite dumb, to fall for this trick over and over again. I hope that we really are not that dumb, and that the manufacturers simply assume that if they can squeeze even a few hundred thousand dollars profit from a jiggered version of their medication before they lose the patent, they might as well try it.

The good news is, you are not a guinea pig.  The parent medication of paliperidone is well known to us, so there should be few surprises.

Dr. Phelps