medication conversion question

[norcalmom]

Hi there,

I went to my pcp to talk about changing my pain medication since I had to take more breakthrough meds lately and I have been on the same medication for almost 2 years. I am taking 100 mcg of the fentanyl patch along with Norco prn. I am having pain on the arm I had surgery on 4 months ago and it feels like my arm is being crushed, twisted, burning, very sensitive etc...

My doctor told me at first I had 2 choices of meds I could try. Either Methadone or Morphine. After she talked to a pain specialist they came up with a plan for me to take MS Contin 15 mg 1 pill twice a day along with tappering of the fentanyl patch that would go on for two weeks 2- 75mcg patches 1 every 48 hours. Then 2- 50 mcg patches 1 every 48 hours and finally 2- 25 mcg patches 1 every 48 hours. After the patches were gone I was suppose to go to 2- 15mg Ms Contin 3 times a day.

I was doing fine at the 75 mcg patches, but with the 50 mcg I started feeling like the MS Contin was not helping as much and then with the 25 mcg patch I felt like it was helping at all.

My primary care doctor after I told her that the MS Contin at the dose I was prescribed didnt seem to be working her response was that the only choice I had was to go back on the Fentanyl 100 mcg. She did say that she doesnt have the staff or time to handle the needs to monitoring the dosage and that I should see a pain specialist. In the meantime she wanted to keep me on the same MS Contin or back on the patch. I decided to go back on the patch and to follow up with the pain specialist to change meds; there was no way I could do it alone on 3 -15 mg Ms Contin a day with my pain at the level it was.

My question is for anyone who knows or has experience with changing from the fentanyl patch to a different med; if he 100 mcg patch is comparable to taking 90 mg of the MS Contin?

Sorry for the long and probably confusing message.

Thanks,
Patty

[Pharmacist.steve]

The conversion range is rather broad 100mcg fentanyl = 240 -500mg of oral morphine... if you have been on 100mcg Fentanyl patches... 45mg of oral morphine is not going to be anywhere close to what you need..

[jtroy]

Hey Patty:

Steve is dead on here...there is a cross-tolerance issue that may be in play here relative to what the pain specialist suggested for you. I know that my pm doc has mentioned that he finds this to be common with his patients on the Fentanyl patch. A basic explanation would be that sometimes when you switch opioids (opioid rotation as you did) the "new" opioid requirement is lower than what you would require. It looks like Steve's numbers are dead on for a range that would include a 50% cross-tolerance which is about as high as I've heard folks here ever have success with. So, basically going to 90mg of oral Morphine would have been like you cutting your Fentanyl patch down from a 100ug/hr patch to a 25ug/hr patch....it's no wonder that you have severe pain doing this.

I'd tend to agree with your doc...you should probably think about going to a pain doc at this point in order to get relief. You've been stable on the patch and your bt meds for 2 years and are now needing more bt meds to keep the pain in check. Perhaps there is some tolerance going on in addition to added pain as well. Either way, it sounds like your pain is horrible and I'd certainly want a pm doc if I were you.

Hopefully this info helps some. Wishing you all the best.

Regards,

T. Jones, DVM

[Lil E]

If you are near S.F. my PM is very good. His web site is www.wayneanderson.net

[911]

is there a site that shows conversion rates for all pain meds???

[mrsdoubtfyre]

http://www.globalrph.com/narcoticonv.htm

there are filters here because of spam.

So this is an expanded typed version that you will have to
retype yourself if they **** out the link.

w w w . g l o b a l r p h . c o m /n a r c o t i c o n v . h t m

This website has other interesting things too, so look around.

Converters do not take into consideration personal metabolic differences, or tolerances. They are estimates only.

[norcalmom]

Thank you to everyone who replied. I was having a hard time to tell my primary doc that the new medication wasnt working or that I actually felt like it wasnt enough. I hate to say that I think I need something stronger because it makes me feel like Im a drug seeker.

I had been on the fentanyl patch for almost 2 years now and I thought that because I had to take more break through pain meds that it might be time to try a change in medication. So at the time of my medication change I was having increase pain and my doctor told me SHE feared that what she was starting me out on might not be strong enough, but that she could change it as needed. It all sounded good on paper and I was on board knowing that I could have some bad days.

I was half way through the tappering when I noticed that the ms contin didnt seem to do anything and I had called her and hadnt recieved any call back for several days. After 5 days I coudnt take it anymore and called back to find out what I should do since I was on my last patch and I would be on my own with only the ms contin. I dont know what happened to our plan, but she was real short and told me that she didnt have the staff to monitor my medication levels and that my only options were to stay on coarse with the ms contin or go back to the patch. It really wasnt an option for me so I decided to go back on the patch and I asked for a referral to see a pain specialist.

I could tell that my doctor was having a very busy week and on top of it she only works part time so I gave her time to get back to me, but after 5 days of being in pain I thought either something had to be done or I was going to have to go to the ER. It was just strange that we had a plan worked out, but she changed her mind somewhere without discussing it with me. This is not the first time she had changed our treatment plan or forgot what we discussed we were going to do. I know she is very busy and even her medical assitant told me she works only half time and she is bad at getting back to messages. I really hate to start all over with a new doctor when I have been through so much with this one.


I just had to vent a little about what happened. Thanks to everyone who replied. It was very interesting how the conversion was not EVEN close to what I was taking. Next time I will have to ask more questions or get a treatment plan in writting I guess.

patty