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margale 01-26-2006 12:18 AM

Conversion from Avinza to Fentanyl Patch
Hi, this is my first post here.

I've been treated for severe fibromyalgia for the last 3 years. At that time, I was led through an exercise by a PT that SEVERELY twisted my trunk and tore all the muscles, ligaments and fascia on my sides and my mid-back. The pain was UNBEARABLE for about a month, and shortly thereafter settled into a chronic pain, all over my body, and specifically in my sides and back. I cannot stretch my trunk at all, lift anything over 5 pounds, push a vacuum, bend sideways or backwards in the least. I cannot even sleep in a bed because of the pain.

For the last 2 years, I have been prescribed 60 mg Avinza in the morning, and 30 more Avinza in the afternoon. Additionally, I take Endocet 10/325 once during the day and 2 at bedtime. And Neurontin 300mg 4x daily. Also Lunesta 3 mg for sleep, and Zanaflex 8 mg at bedtime.

Today, my regular doctor gave me an Rx for 100 mg Fentanyl patches to REPLACE the Avinza, keeping all other meds the same.

I just wanted to do a "sanity check" with other sources before I switch over to this highest dose of Fentanyl.

Any thoughts?



catnap 01-26-2006 09:48 AM

Re: Conversion from Avinza to Fentanyl Patch
Hi Margale:

I just want to tell you WELCOME to the forum and this is a GOOD bunch of folks we have here will all kinds of experiences to share with you. You will become quite educated if you stay with us! At least I think you will. :)

Going by the conversion chart I have, and this is a Fentanyl patch conversion chart. A 100 mcq patch q72hrs. is equal to a 315-404 mg. oral dose of morphine (Avinza). I was on 100 mcq. patch q48hrs. with 6 - 7.5 lortab q24hrs. and changed to Avinza. I take 480 mgs. q24hrs. now. I was started at an inappropriate dose of 120 mgs. q24hrs. causing me withdrawal and titrated up over a period of 3 weeks until I got to the appropriate dose.

Anyway back to your dose. By adding together your doses of Avinza and Endocet you are at a 150 mg. q24hrs. right? That means a 100 mcq is quite a bit higher than you should start with. A 50 mcq patch would be equal to 135-224 mgs. morphine (Avinza).

If you put that patch on it will peak in about 24hrs. going by the pamplet they put in the box of patches. You should start feeling the effects at 7-12 hrs. and will take 17 hrs. to be out of your system. I think this might be too large of a dose to begin with. Call the doc and remind him of what you were on. If you haven't put the patch on yet, dont. :nono:


BTW after my spine surgeries I went out and paid $1000 for a mattress from on the advice of my neuro doc. I even put a extra feather mattress on top. I can't sleep on it. :rolleyes: I haven't slept in a bed for 10 years. I have a recliner.

Shoreline 01-26-2006 09:52 AM

Re: Conversion from Avinza to Fentanyl Patch
Hi Tom, There are charts out there called equianelgesic conversion charts that some docs use as a reference. However the charts are just ballpark guides. You may end up in the parking lot or in the obstructed veiw seats. :)

Some factor in a cross tolerance percentage or allow a doc to do this, meaning because it's a new med, hopefull you will respond better so less can be used, a med can always be adjusted but I understand your concern going from a relatively low dose of Morphine to the strngest patch. Although the 100ugh patch is the largets they make I have met folks that wear 4-9 at a time plus use other long acting meds. It simply takes what it takes.

Tee best chart on the net I had seen doesn't seem to be available right now but there is other infor out there. Some docs may use the PDR some may use palm pilots with programs for conversion and some may use their experience or the Brietbart method.

If this is a PM doc that made the conversion, I wouldn't be too concerned. If it's your GP doing this it would have me a little concerned because it is a med GP's don't noramlly use, not that the dose is outragous when you factor in and look at everything.

However we all respond differently to different meds. Fentanyl wasn't effctive for me, so I could use lots of 100ugh patches and achieve sedation before I got pain relief that I could still function with.

I did do some checking and it's really not that out of line based on the PDR and other guidelines. If you factor in your BT med use, add another 45 mgs of morphine based on 30mg of oxy used daily. I'm using a pretty standard 1:1.5 conversion from oxy to morphine. This brings your daily morphine dose up to 135 mgs a day.

You also have to consider that when you take 20 mgs of oxycodone in a single dose at night this significantly increases your serum level and effect of opiates. Proportionally that's a huge dose of BT meds when it increases your serum level 6 fold rather than 20-30% that most docs use for BT. If you can manage the respirtory supression of taking the additional 20 mgs of oxy for 4 hours at night, you can safely manage it throughout the entire day.

If you were to take 20 mgs of oxy every 4 hours that would be an additional 120 mgs of oxy per day or 180 mgs of morphine. If you converted all the oxy we already know you can tolerate, to Avinza and add it t the 90 you already take, This would bring your dose to 270 mgs of Avinza a day and sustain roughly what you feel after taking your BT meds at night. You have that same level during those 4 hours and it hasn't hurt you yet, so why would it hurt you if you had that same level constantly. The only unknown is the cross tolerance variable. I may take very little Fentntyl compared to morphine or Fent may not be effective and youmay have t take twice what some cahart says, it's all just part of the fun of trying new drugs.

That totally changes the picture, You know what you can tolerate in avainza plus BT meds, This means your tolerance is much higher than what 90 mgs of Avinza actually sustains in your sytem if you can safely take 20 mgs of oxy on top of the Avinza. Wait and see how things go before using any more BT meds just to be safe.

The Brietbart method suggests Converting every 2 mgs of oral morphine per day to 1ug of Fentanyl, THis means the combined 270 mgs of morphine per day you know you can already tolerate, equates to 135 ugh of fentanyl or a dose between 125ugh-150ugh.

Patches take about 17 hours to reach peak effect, Ideally you should have someone there when this happens, your spouse, a friend, family member, anyone, should you find you have difficulty breathing or experience other side effects.

Based on your abilty to tolerate the oxy on top of the avinza, most likely you will feel closer to how you feel after taking the 20mgs of oxy at night all the time. IF this is a dose to simply allow you to sleep, you may have to cut back to prevent the meds from causing more impirment then your condition. IF the meds just make you sleep all day, that's not productive and most docs, and family member won't go for it, and you would get tired of sleeping your life away after a ferw months too. The goal is to shoot for improved function, not total pain relief. If your unable to work, even the higest doses of opiates may not allow that. I hav a ump and when you compare pump strengthto oral strength myd dose would probably sound astounding. BUt at best it allows me to function around the house, It takes 8 hours to knock out 2 hours of houswork, But I get it done in little pieces resting when my legs start to shake.

Another reason I say it doesn't sound outragous aside from charts is that the dose your on now isn't working. When the dose isn't working, you can handle a much greater increase than you would make compared to when you're simply fine tuning a dose for max effect with minmal side effects. You can safely double most doses of medication other than methadone that continues to build up for 5 days. It honestly sounds like they are trying to give you much better relief throughout the entire day, and the only thing preventing them from increasing the dose is if your still not getting relief are the side effects.

If it' makes you too drowsy, or causes Urinary retention or any other unpleaseant side effect. But just because 100ugh is the largest patch it definitely doesn't mean that's the highest dose anyone should ever use. Even in clinical trials they tested hundreds of micrograms per hour.

Here is some info on converting to fentanyl, including the PDR method.
[I]Convert the oral morphine dose to Duragesic-there are two methods:
A. Standard Table: look up fentanyl transdermal in the PDR, find the morphine conversion table, it says that 135-
224 mg of morphine = 50 mcg patch. Note: this range of morphine is very broad which may result in significant
under dosing.
B. Alternate Formula: In 2000, Brietbart et al published an alternative method, based on the results of a multi-center
trial by Donner et al, that relied on a fixed dose conversion ratio to calculate the fentanyl transdermal dose.
Brietbart recommended the ratio of:
2 mg oral morphine = 1 ug of fentanyl transdermalórounded to the nearest patch size. In the case example above,
216 mg of oral morphine is approximately equianalgesic to 100 ug fentanyl transdermal.
Note: using this formula, 25 ug fentanyl transdermal is roughly equivalent to 50 mg oral morphine/24 hours. This
dose may be excessive when used in an opioid naÔve patient and/or the elderly.
Key Considerations
1. All equianalgesic ratios/formulas are approximations; clinical judgment is needed when making dose or drug conversions.
2. The risk of sedation/respiratory depression with fentanyl transdermal is probably increased in the elderly or patients with
renal impairment due to its long half-life, thus, choose the lower end of the dosing spectrum.
3. When in doubt, go low and slow, using prn breakthrough doses generously while finding the optimal dose.[/I]

I hope things work out and this brings you more relief but anytime you start a new med, docs should be prepared to see you more often, If your still miserable after 2 or 3 cycles, let him know. If it's simply too sedating in the day time, you need to let them know about that too.
Take care, Dave

catnap 01-26-2006 10:10 AM

Re: Conversion from Avinza to Fentanyl Patch

I found a conversion chart at GlobalRph that I showed to my doc on my dosing. I thinks is pretty accurate. At least it was in getting my doseage right. The dose I was at was 449 mgs. q24hrs. and now I am at 480 mgs and doing better than I was except for the damn constipation. That's something I have never had to work at before, but I am dealing with it. If you know what I mean. :rolleyes:

Your friend,

margale 01-26-2006 11:03 AM

Re: Conversion from Avinza to Fentanyl Patch
[QUOTE=catnap] If you haven't put the patch on yet, dont. :nono:
....... I haven't slept in a bed for 10 years. I have a recliner.[/QUOTE]

I did NOT put on the patch. THANK YOU!! We live over 100 miles from any major city, and the nearest small hospital is a good 1/2 hour away driving at 70-80 miles an hour... Not a good situation for new medicine problems, especially the type from opiates like these. I've talked to my pharmacist now, who agrees (the one on duty last night did not know) that 100 mcg "might" be excessive. I've also put in a call to my GP, who was the one who prescribed it. The clinic in which my PM worked (120 miles from my home) CLOSED, so I was out of luck for pain providers.

I decided to search for answers on the net last night, and found you nice folks. THANK YOU SO MUCH!

Carol, as for recliner chair, that's what I use ... a "Zero Gravity" recliner that my wife purchased for me at Relax the Back over 12 years ago. It works great! And for the constipation, I've found, after extensive personal testing :( :rolleyes: , that MIRALAX (17g propylene glycol) is my miracle constipation drug. It softened up everything nicely ... if you haven't tried it, I recommend you check with you doc for a sample. Wonderful stuff!

[QUOTE=Shoreline] . . ."it's all just part of the fun of trying new drugs. . . .

Patches take about 17 hours to reach peak effect, Ideally you should have someone there when this happens . . [/QUOTE]

Dave, thanks for the TREMENDOUS amount of information. It really helps!

As I've mentioned above, it's a little dangerous for me to fool around with medicines up here (coast of Oregon) with medical facilities being so far away. I think a conservative approach is more appropriate. It sounds like a 50 mcg dose might be better to start with, using my Endocet for BT pain.

I really feel welcome here, guys! I wish I had found this forum years eariler!

Regards and sincere thanks!


Shoreline 01-26-2006 11:50 AM

Re: Conversion from Avinza to Fentanyl Patch
Hey Carol, You have to remeber that conversion charts are just ball park. The fact that Tom can tolerate The combined BT dose and the avinza, suggests that he can tolerate that same dose around the clock safely. In fact with the night time dose he's taking even more respirtory supressives like lunesta, 8mgs of Zanaflex and Neurontin.

If that dose is safe for 4 hours at bed time, It's safe around the clock. It may be too impairing for day time use but it's still safe. Can he function in the day time on the 100ugh patch? That's just trial and error but when you look at The night time dose he tolerates, the severity of pain and lack of relief from the present meds. An equianalgesic dose provided by that chart, it simply provides the equally same poor relief. So why not increase if you can barely walk and know what you can tolerate.

I don't know why anyone would leave the BT meds used every day at the same dose out of the equation when caculating safe tlerance. So many people simply incorporate the BT meds into a daily regemin thare are just part of your daily opiate intake. Which makes the BT meds ineffective when you truly need them. The same BT dose of 20 mgs very nigt for 6 months isn't going to do squat if you have a flair because it's no longer an increase in what you have become used to taking.

Using the highest known tolerated level that still doesn't provide proper relief as a starting point makes more sense than using a chart that doesn't take any of those factors into consideration. I don't think the docs goal was to provide equally poor relief.

What you take and what I take really has little to do with what will bring someone else relief. But from a safety standpoint, 100ugh isn't a huge increase from the the time of day when he adds 20 mgs of oxy to the avinza. I think that's Toms' concern. AS far as finding relief with tolerable side effects, that's trial and error.

THat particlualr chart your using also compares methadone to morphine aproximately 1:1 and I have switched back and forth 3 times between meth and morph and ended up at 5:1 each time. Meth being 5 times stronger than that chart suggestted. Charts are simply meant to prevent withdrawal and respirtory arest. When you in that kind of pain, you have to look at the big picture.

I used the same method in adjusting my pump. I have a daytime rate and a nightime rate. If I can tolerate the higher nightime rate without impairment or intolerable side effects, I switch my day rate to the night rate and increase the night rate. My doc allows me to calcualte my own increases, I give him 2 or 3 options but I always use what I have been exposed to as a guide to what I can tolerate. Just because his Avinza rate is low, you still have to look at what Tom takes and tolerates safely every night before saying a dose is unsafe.

He's obviously tolerating a much higher dose in the evening. 90 mgs of avinza really isn't a high dose, Your talking about dividing 90 mgs by 24 hours or into 6 15 mg short acting doses. When you through 20mgs of SA OXY or 30mgs of SA morphine on top, your talking about a dose equivelent to 45 mgs of morphine every 4 hours, what does the chart say if your daily dose is 270 mgs of morphine a day, we know he can tolerate that by his night time use.

If that still isn't providing relief, why not be more agressive and take all factors into consideration. If that level is safe at night, it's safe in the day. It just comes down to being functional and the side efects. Add in the other 10 mgs of BT Oxy your talking about a patient that is used to having the equivalent of 15-45 mgs of SA morphine every 4 hours, Times 6 your talking up 270-285 and still not getting relief. What does the chart suggest then.

Basically I'm saying look at the 4 hour period in which he has the most medication on board, if that is providing relief, shoot for that in a LA form. If that's not enough then expect to increase. He's obviously under medicated at this time and used to having 3 times what the avinza provides every night.
Take care, Dave

margale 01-26-2006 12:21 PM

Re: Conversion from Avinza to Fentanyl Patch
I heard from my doctor within an hour of placing a call to him. His opening statement, "I'm not trying to kill you, Tom!".

He factored the BT meds into account when he prescribed the 100 mcg Fentanyl patches, just as Dave has theorized here. BUT, he also agrees that a more "moderate" approach to a new medicine is probably best. He told me to keep the 100's and has an rx waiting for me for 50 mcg patches. Since I've been on the Avinza/Endocet combo so long, I'll wait until I'm off from work next Thursday-Saturday before trying them.

BTW, my reason for suggesting these changes is that taking the morphine/Endocet combo, in concert with moderate to severe diverticulosis and IBS, virtually guarantees that I need to spend the first 5-6 hours of each day in or near a bathroom. 3-8 bowel movements have been the norm. It takes that long to empty the bowels. And I can't do anything to "hurry up" the process. Luckily, my work allows me to come in to work at Noon each day.. I was hoping that the Fentanyl would not be quite as bad as the current combo.

Before I started these meds, I had some pretty active mornings. Not so now..

Thanks again for all the help!


catnap 01-26-2006 02:00 PM

Re: Conversion from Avinza to Fentanyl Patch

Maybe you will find like I did that fentanyl is not as constipating as the morphine. That is better he gave you the 50s. You can gradually increase the dose every three days until you get relief with the pain. You still have your bt meds to take to help in the meantime.


I know these conversion charts are low and I did take the bt med into consideration. But I still say once he puts that 100 mcq patch on and if it disagrees with him there is very little he can do until it wears off other than going to the hospital treatment if need be. I averaged the fentanyl at 404 mgs. with present opiate at 150 mgs and that is a 254 mg increase. I only presented my dose in comparison with how my doc changed my meds inappropriately.

The way he should have been changed over was to calculate his last 24 hr. dose and give 1/2 of the new med and 1/2 of the old med, gradually titrating up with the new med and decreasing with the old med. That is the only "safe" way to do it. This is a new med to him and he doesn't know how he will react. If it were me I would say yes go ahead with the extra 254 mgs. I know I can handle it because I have taken fentanyl for years. But to someone new with it I would rather go for the lower dosing (50 mcq patch) and titrate up every three days until the pain got under control.

When you live out in the country far away from your doc and a hospital I would go through a little withdrawal and having the meds available in smaller doses to take than to put on a patch with such an increase not knowing how I would react and possibly overdosing or having to travel to a hospital for treatment.

But that is only my opinion and that is all I can give here. I have only an EMT certification (expired now) in the medical field. So all I can do here is share my experience about pain and pain meds.

Your friend,


You are going to find a much better class of people on this board than on the other board that I cannot mention the name of. Dave and I have sometimes have a difference in opinions, just like any other group of people but I love him all the same. :) Shoreline (Dave) is usually the first one I ask if I need help. He has done a lot of research about meds, spine problems, etc. He is virtually an encylopedia (sp?) of knowledge.

Anyway glad you joined us and keep in touch. We cpers stick together and help each other out! :wave:


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