| WickedNoah |
| (Member) |
| 10/15/04 05:53 PM |
 Re: Avinza
|
Quote:
The only thing that I have read in my nursing studies about morphine is that once it travels into the digestive tract, you actually lose approximately 50-60%. This means that you actually only get about 40-50% of actual medication. I think that this theory is probably true of most oral pain medications. The best route for pain relief is through IM or IV administration. I don't know why doctors don't factor this into consideration when prescribing oral pain meds. I know that my husband got very little relief from the Avinza. The doctor now has him on 4mg Dilaudid 4 times/day and he is much better with this.
Well, morphine is a special case in that, unlike other pain meds, it's targeted by the recently-discovered UGT system that tags it for removal from the body. The UGT system is so new that most textbooks give it only a passing mention, but original papers (found by searching on Pubmed, at ncbi.nlm.nih.gov/pubmed) are of course up-to-date and if you can stomach their jargon, you can gain a lot of info that books don't have. Most meds (of any kind) are metabolized to varying extents by the cytochrome P450 system in the liver and other cells. But, only about 5% of morphine is metabolized by these enzymes, so it is definitely a very different situation.
By the way, the 50-60% for morphine that you read about can be as low as 15%, depending on what book or study you read. It makes your proposal for more IM or IV administration even more enticing. The problem is, patients will always mess this up and hit a major vein or artery if they do it themselves...
I need to add, though it sounds like I'm talking down, that you can't make the generalization that 50% of most meds make it through untouched - hydrocodone, for instance, may NEED to be metabolized to become active, while the benzodiazepine temazepam (Restoril) isn't metabolized at all. You get a whole range of data actually, from 0% with temazepam to 98% with BusPar. Each drug has to be treated differently; there's no finger rule here.
I'm just saying this b/c I'm a neuroscientist with a degree in neuropharmacology and I see this all the time.
Noah
