switching from oxycontin to methadone

Katillac, RN · Nov 11, 2005

:rotfl: help!
should we start the methadone at the next oxycontin dose time? say- after waking up in the am? any problems with gi distress? may it be inserted rectally, like mscontin?

great articles on methadone from the who:

http://www.whocancerpain.wisc.edu/eng/18_1/interview.html

http://www.whocancerpain.wisc.edu/eng/16_1-2/alternatives.html

also this one on rectal methadone specifically:

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&list_uids=8589026&dopt=abstract

we have used it rectally by grinding a tab and putting it in a gel cap. either the generic or the name brand (methadone/methadose), and i can't remember which, is too big and too fragile to be used rectally, therefore the crushing and caps.

it is said to cause the same gi problems as other opioids, nausea and constipation being the biggies. i have only ever used it with pt's that were switched to it from high doses of another opioid, and i have not noticed any gi sx problems.

as for dosing, there is one school that says d/c the ms04/oxycodone/fentanyl and at the first c/o pain, give the prn, and then give it prn as frequently as q3 for the first five days, after which time you divide the total given for the five days by 5 to get the appropriate 24 dose which of course you then divide by 3 to get the q8 dose, and the prn from then forward is 10% of the 24 hour dose. i don't like that dosing, because what's the point switching off a well established and effective long acting med to go to a med that the pt may need prn q3, even if it's only for a few days? a day in pain is a day too many.

other practitioners start a q8 dosing when the med the pt is being switched from is due. does that make sense?

flea · Nov 12, 2005

yes, thanks!! We're switching Mon AM. The pt has intermittent pain, takes 4 BTP doses in 24 hrs, but becomes confused and oversedated when the oxycontin was increased.

Hope it goes well, thanks again!!

doodlemom · Nov 12, 2005

:rotfl: help!
should we start the methadone at the next oxycontin dose time? say- after waking up in the am? any problems with gi distress? may it be inserted rectally, like mscontin?

we start it at the same time the next dose of oxycontin or ms contin is due. it may be inserted rectally. we use the 10 mg/ml liquid and give it sl. if they are needing a much larger dose than say 20 mg, then we'll give it in tablet form rectally (if unable to swallow.) i had one patient that was on 90 mg!!! q 8 hrs and we had it compounded into a suppository when he was no longer able to swallow. this same patient had been taking ms contin 800 mg q 12 hrs prior to being switched over to methadone. i haven't noticed any more gi problems than with other narcotics.