Methadone -vs- Morphine, Study Results

gwenith, BSN, RN · Jan 20, 2004

Thank-you Dave. Although I deal primarily with acute pain issues (ICU/CCU) it is always good to keep up to date.

adrienurse, LPN · Jan 20, 2004

I understand that there are people who have ideosyncratic responses to narcotics, and I understand some people have true allergies to morphine, but why Methadone as a first line treatment? Please explain this to me Dave.

This line of thinking may be out of date (I'm referring to literature from the late 90's here). Methadone was not recommended for chronic pain and although it was known to have a longer duration than morphine, it's effect and half life was seen to be unpredictable. What's wrong with other sustained release preparations? Also, doesn't prescribing methadone require a special licence in your neck of the woods? Doesn't it require special supervision?

LilgirlRN, ADN, RN · Jan 20, 2004

http://opioids.com/index.html

This is kinda a science/druggie website. I've posted it here before, it has all kindsa good opiate information however, may be useful to some folks here. :) WR

Dave ARNP · Jan 20, 2004

OKkkkeyy dokkkey....

Now, everyone take seat, get a notebook and listen closely while I try to put what I know into a way someone can understand:D

(It can and usually is quite comical!)

I'll try to answer your questions and then you can hit me back with the questions that have come up based on the little sense I've made.

Firstly, to prescribe Methadone in an addiction treatment program DOES require a special DEA licensee. I'm not exactly sure on what sort of qualifications you must hold, but I assume you must be an addiction specialist.

HOWEVER, to prescribe Methadone for treatment of pain, does NOT require a special licensee. It falls under the same rules and regs involved in prescribing Morphine, Oxycodone, Demerol and other CSII substances.

Now, what you are saying about Methadone is half sorta almost right. Methadone has a long half life. Dose for dose it last about twice the time as MSIR. Sounds good, doesn't it?

The problem is, patients often do not get a full "half life" of pain relief from Methadone. This also is common with PO Meperidine and Darvocet. The issue with Methadone loosing its effectiveness shortly after the dose, can easily be offset by giving the medication TID-QID, being careful to not overdose the drug as it's metabolites can accumulate and result in resp depression and other CNS side effects.

The only other issue I've seen with Methadone is the difficulty in trying to convert it to another strong opioid. Since it does have varying absorption, there are no good (atleast I've not seen one) charts that you can easily look at and say "20mg of Methadone equals 20mg of MSIR". Conversion usually has to be done by trial and error, erroring on the side of too little.

Because of Methadone's low cost, and great strength, it is a wonderful tool in the treatment of chronic pain. While Morphine remains the gold standard, Methadone certainly has its place.

Feel free to comment and question at will :)

Dave

**canoehead, BSN, RN** · Jan 20, 2004

How is the transition period from MSSR to methadone? Should patients expect to be in increased pain during that period (how long a period are we talking about). What breakthrough meds can they use?

A patient has the side effect of getting almost narcoleptic after forgetting to take scheduled MSIR- will this effect go away with methadone? what other/new side effects can he expect?

What meds can be taken for everyday pain, like headache? Tylenol or Motrin are effective now.

Do physicians need special training to help with the transition? What about monitering organizations-will they give an MD trouble if the pt is already on an effective dose of MSSR? In our community all Rx for narcotics can be reviewed and some MD's have lost their ability to prescribe because they were writing scripts inappropriately.

I will PM you, but thanks for your help.

adrienurse, LPN · Jan 21, 2004

Thank You professor Dave. So if accumulation of metabolites is a concern (much like meperidine), it probably isn't as safe for the frail elderly as MSIR.

Tell me for what conditions and what populations you tend to prescribe methadone.

Dave ARNP · Jan 21, 2004

You're very correct that it's not best for the elderly.

NONE of the longer acting drugs are good for the elderly.

MSIR and Actiq are still my favorites for elderly in the strong opioid groups. Percocet and Vicodin are good as well.

Now, as far as conditions I use Methadone in:

Fibromyalgia, OA/RA, Burns, CA (Varying types. Almost always use Duragesic for Lung), most neuropathic pain syndromes, ms pain, myofacial pain and in many cases where pain is expected to persist for long periods of time after surgery. Essentally its a big chronic pain drug for us, but also plays a role in acute and CA pain.

If I were going by what we perscribe it would be:

1. Vicodin/ES/HP

2. Methadone

3. Oxycontin & Percocet (these would tie in what we write)

4. MSIR

5. MS Contin/Kadian

6. Duragesic

The new up and comming drug for is Actiq. TOTALLY loving the results that I'm seeing with it.

Dave

aimeee, BSN, RN · Jan 21, 2004

Seeing the above discussion regarding metabolites of methadone sent me searching, because although I have no personal experience with methadone, I have been very interested in it and have done a bit of reading on it and I thought I was remembering that metabolites were not a problem but that the long and variable half-life were what led to the toxicity problems.

I found this in an article on Medscape:

"Methadone accumulates with repeated dosing because of its long half-life of 17 to 128 hours, and it has enormous interindividual variability in clearance. It is recommended that this drug be prescribed as needed during initial titration to avoid excessive side effects during the titration period. There are no known active metabolites of methadone, which makes it attractive for patients at risk for toxicity associated with metabolite accumulation."

and this from the American Pain Society Web site:

"First, methadone has no active metabolites. Much of the toxicity associated with other opioids (e.g., morphine, hydromorphone, meperidine, and fentanyl) is the result of metabolite accumulation. Methadone would therefore be a logical choice for the patient experiencing, or at risk for, toxicity associated with metabolite accumulation. Second, because of incomplete cross-tolerance, methadone is an appropriate alternative when intolerable side effects to another opioid have limited further dose escalation. Third, methadone is very inexpensive. Fourth, methadone's long duration of analgesia with chronic use allows less frequent dosing than with other opioids."

http://www.ampainsoc.org/pub/bulletin/sep00/upda1.htm

Dave ARNP · Jan 21, 2004

Very glad you caught that Amiee!

When I was trying to explain about Methadone accumlating, I think Metabolites where just what came to mind, as that is the main concern with other like subtances.

Lemme try this again.

Methadone DOES build up. Very much so. It takes several days to a week in order for a patient to achive the level of effect that they're going to get with Methadone. This is mainly because of the variability in what amount of the drug is excreted, and because of the varried half life. Persay a patient gets a 24hr half life from the drug. You build on the dosage, until the amount of drug remaing in the system after excretion is equalled out by what sort of half life the patient is going to have. Thus, a 10mg dose for patient a, may be equal to a 40mg dose for patient b.

Good evidence of this is shown with patients who have an allergy to Methadone. The patient may abruptly stop the drug per order, but the residual effects of the drug can last for many days. I've had more than one patient scratch themself senseless waiting for the drug to be completely cleared from their system.

Additionally (while on the subject), while Methadone is very closely related to Morphine, an allergy to one does not equal an allergy to another. Increased chance of an allergy, yes. But many patients will do very well on MS when they have a bad reaction to Methadone.

Dave, who hopes he's made a little more sense.

Nurse-k-99 · Feb 5, 2004

I take 190mg of methadone QD. My pain leval is great I do find the need to split this dose at times but for the most part it works. I have a dul diagnosis. Due to the pain I am in I was given 80mg Of oxycontin TID. The more I used it the more I needed an increase. It got to the point that this medication did very little for my pain. I tried decreasing the dose but found the withdrawals were intoloble. So I found myself with a dependency as well as in a gret deal of pain. Because of the dependency I was forced to go to a methadone clinic to seek treatment. As was stated Doctors can RX for pain but not for addiction. So I stand in line with other oxycontin dependent people as well as heroin addicts to recieve my daily dose. I have earned four takehome doses this allows me to split my dose to manage my pain. Can anyone see anything wrong with this treatment?(please excuse my spelling error's I have been up almost 20 hours with a sick new born. Thanks Kelly:o

Dave ARNP · Feb 5, 2004

Hum...

Just that someone with chronic pain is being treated in an ADDICTION PROGRAM!

Sounds to me like your care is being provided at the WRONG place. JMHO

Dave :devil: