Incomplete cross tolerance

Are you talking about the globalrph.com narcotics calculator?

Here is one explanation of Incomplete Cross Tolerance from Northwestern.edu

• While pharmacologic tolerance may develop to the opioid in use, tolerance may not be as marked relative to other opioids

• Incomplete cross-tolerance is likely due to subtle differences in:

• The molecular structure of each opioid
• The way each interacts with the patient’s opioid receptors

• Consequently, when switching opioids, there may be differences between published equianalgesic doses of different opioids and the effective ratio for a given patient

• Start with 50% to 75% of the published equianalgesic dose of the new opioid to compensate for incomplete cross-tolerance and individual variation, particularly if the patient has controlled pain

• If the patient has moderate to severe pain, do not reduce the dose as much
• If the patient has had adverse effects, reduce the dose more

• An important exception is methadone, which appears to have higher than expected potency during chronic dosing (compared with published equianalgesic doses for acute dosing)

• Start with 10% to 25% of the published equianalgesic dose

Titrate appropriately to achieve pain control.

However, I think if you're just trying to convert X amount of codeine to X amount of hydrocodone, enter 0% for the incomplete cross tolerance.  

Gtrplayer

I think, if you just put 0% for the cross tolerance, it will tell  you roughly how much oxymorphone is equal to X amount of oxycodone.

I just entered 30 for the amount of mg for oxycodone, with a 0% cross tolerance rate, and converted it to oxymorphone.  The converter said that 30mg of oxycodone is roughly equal to 15mg of oxymorphone.  Therefore, oxymorphone is roughly twice as strong as oxycodone.  But, keep in mind that there are different preparations of oxycodone, such as oxycodone extended release, regular release oxycodone, and oxycodone + acetaminophen.  So the converter, while a very useful tool, doesn't really address the differences in long acting oxycodone and regular acting oxycodone/oxycodone+acetaminophen.

Does that help at all?

Gtrplayer

 You're welcome, MUDBONE.  I wasn't sure if that was clear as mud or not.  I'm glad I could help you.

Gtrplayer

Here is a link to the Narcotic's conversion program from Globalrph.com

If you click on the second link, you will see a list of other converters available on that site.

Gtrplayer