Tag: opioid tolerance

Tapering off Buprenorphine or Suboxone, Pt 2

In the last post we discussed some of the misconceptions about tapering off opioids.  Today we will discuss a couple basic principles, and then describe the approach I recommend for my patients tapering off buprenorphine.
Opioids act at receptors that normally bind endorphins, which are released by neurons in response to a range of stimuli including trauma and rewarding behaviors such as eating a good meal or using addictive drugs.  Endorphin pathways elevate mood, reduce sensation of pain, and impact urine production, immune function, intestinal motility, and other bodily functions.  Endorphin pathways have a certain baseline activity or ‘opioid tone’ that is directly related to opioid tolerance.   When opioid stimulation is greater than one’s tolerance, opioid tone is increased.  When opioid stimulation drops below one’s tolerance, opioid tone is reduced, causing withdrawal symptoms.

The goal of any taper off opioids is to recover original or native opioid tolerance.  Some people focus on getting rid of the opioid, and even use substances or behaviors to ‘flush buprenorphine from the body’.   Products marketed as detox agents have minimal impact on the clearance of buprenorphine or other substances.  And even if they could increase the rate of clearance,  they would only make detox harder by increasing the severity of withdrawal symptoms.  The relatively slow metabolism and clearance of buprenorphine provides a cushion by slowing the loss of opioid tone.

Prolonged use of any opioid changes opioid receptors.   The changes are not fully understood but include a decrease in number of receptors and changes in binding properties that reduce receptor sensitivity to opioids, including endogenous opioids (endorphins).  Recovery from a state of tolerance takes 2-3 months, and is initiated by reduced opioid tone.  Withdrawal symptoms reflect the reduced opioid tone that provokes eventual recovery of native tolerance.

Recovery of native tolerance is the rate-limiting step when tapering off any opioid, including buprenorphine.  When the dose of buprenorphine is reduced, the amount of buprenorphine at opioid receptors decreases over the next 5 days and then stabilizes at a lower level.  In response, opioid tone (the summation of current flow through opioid receptors) drops below normal.   If the dose of buprenorphine is maintained at that level, opioid tone will recover to normal in about 2-3 months.  If buprenorphine is suddenly and completely discontinued, opioid tone will decrease to very low levels and cause severe withdrawal that lasts for 2-3 months.  If buprenorphine dose decreases more slowly, opioid tone will decrease more slowly, lessening the severity of withdrawal.  But it still takes 2-3 months for opioid tone to return to normal.  So for any taper, patients must decide whether to decrease their dose quickly and be done in 2-3 months, at the cost of greater withdrawal, or instead to taper more slowly to reduce the severity of withdrawal.

The relationship between buprenorphine dose and opioid activity is linear up to about 2-6 mg.  Beyond that point further increases in dose have less impact on opioid tone.   The reverse occurs when tapering, so that opioid tone decreases only slightly as dose is reduced from 16 mg per day to 4 mg per day.  The non-linear dose/response relationship allows for rapid decreases in dose early in the taper process with limited or no physical withdrawal symptoms. Since the early challenge is mostly psychological, I use the early part of a taper to help assess whether a patient is truly ready to take on the tapering process.

I like to have patients lead the way in tapering off buprenorphine.  I’ve found that if I lead and reduce the amount of prescribed buprenorphine for the next month, patients often fail to make reductions and end up out of medication before the end of the month.  So instead I ask patients to tell me when they are certain that they are ready to stay at the lower dose.
During a taper, I recommend dosing buprenorphine twice per day.  Patients start by removing 2 mg from the evening dose.    After at least two weeks 2 mg can be removed from the morning dose.  This sequence is repeated at intervals of at least 2 weeks until the total dose is 4 mg per day. In my experience patients who get to that point are usually in a good mental position to begin the second, more difficult part of the taper.

Most people will be able to continue working when opioid dose is reduced by 5% or less every 2 weeks, or 10% every month.  That number is a good general guideline when deciding how fast to taper.  Suboxone film makes tapering relatively easy.  Patients purchase a weekly med organizer, and start the week by opening and stacking 7 films.  A scissors or razor is used to cut a millimeter from the end of the stack, and one film is placed in each compartment of the organizer for that day’s dose.  When the patient is comfortable with that dose, slightly more is removed for the next week.  The process continues every 2-4 weeks, eventually changing to the 2 mg films.  I recommend that patients continue tapering until the dose is 300 micrograms (0.3 mg) per day or less before stopping buprenorphine completely.  It is fairly easy to guesstimate where to cut the film in order to reduce by 10%;  just measure half, then half of that, then half of that.

Buprenorphine tablets, of course, are much harder to divide.  Zubsolv did people a favor by coming out with a range of doses, and hopefully other brand and generic manufacturers will eventually follow suit. For now I usually have patients use the tablets to taper as far as possible, using the 2 mg tablets in the lower dose range, and then pay the extra cost for the film for the final month or so.   A 12 mg film can be divided into 24 half-milligram pieces without too much effort, so the cost doesn’t have to be prohibitive.

I have had many patients taper successfully off buprenorphine.  Fear is common and normal for a number of reasons, but the fear usually gives way to a sense of confidence and optimism when a taper is done correctly.
Things to keep in mind:

  • Be patient.  Tapering by too much, or too quickly, causes withdrawal symptoms that lead to ‘yo-yos’ in dose.
  • Buprenorphine products are very potent.  A sliver of Suboxone Film may contain enough buprenorphine to harm or kill an animal or small child.  Take care to divide the medication in a well-lit setting, and clean up very carefully.
  • Buprenorphine is used to treat pain in microgram doses.  If you jump from 1 mg, you will have considerable withdrawal symptoms.
  • If you are still running out of medication early, it is not time to taper off the medication.
  • People on buprenorphine for a year or less have rates of relapse over 90%.  In my experience patients are more successful tapering off buprenorphine if they have been on the medication for 2-5 years or more.
  • If you struggle in tapering down to 8 mg, consider going back to your stable dose, waiting 6 months, and trying again.
  • People addicted to opioids often substitute other drugs for their drug of choice.  Do not start a new addictive substance in order to get off buprenorphine.

Good luck!

A New Way to Stop Suboxone?

Originally Posted 10/27/2013
I usually have my wife/business partner review my posts and provide her opinion whether my arguments are sound.  For the record, she tells me that this post is technical and boring.  I disagree, but we aren’t planning to separate over the issue.  A valid criticism, I think, is that I’m doing a lot of guessing and wondering in this post.  This post is an example of the things I waste time wondering about.   I try to avoid writing things that are somewhat speculative, but I wanted to give it a shot for two reasons.  First, because there may actually be something to the idea I am about to describe.  But more important, I wish to point out some of the many ideas in the addiction world worth exploring…. And I hope that pharma continues to search for answers (i.e. spend money) in this area of medicine.
So I’ve been thinking more about ALKS 5461, the Alkermes pipeline medication that is a combination of buprenorphine and ALKS 33, which is a mu opioid antagonist also called Samidorphan with the structure shown at the left. ALKS 5461 is being developed by Alkermes for the treatment of major depression.  I don’t know much about the clinical actions of ALKS 33, (a proprietary molecule), except that it comes from a family of drugs that bind with high affinity and specificity to mu or other opioid receptors.  Samidorphan, a mu receptor antagonist, allows investigation of buprenorphine’s potential therapeutic effects at kappa and delta opioid receptors by blocking effects at the mu receptor.  Drugs with actions at other opioid receptors have be developed, and in some case patented.Until recently, theories about depression revolved around abnormalities in brain monoamine pathways or deficiencies of monoamine neurotransmitters.  Monoamines include serotonin, melatonin, and the catecholamines (noradrenaline, dopamine, and adrenaline). Most modern antidepressants act at serotonin or catecholamine receptors or reuptake sites. The new Alkermes medication ALKS 5461 is the first serious effort that I am aware of to treat depression from the opioid perspective.
Our brains contain natural opioids called endorphins and enkephalins.  Endorphins and enkephalins are neurotransmitters in pathways with a wide range of actions, including blocking pain and raising mood during injury or sexual activity. Pain pills such as oxycodone displace endorphins and hijack the natural endorphin pathways, providing euphoria without the trouble of buying flowers.  Of course, a relationship with self-administered opioids always becomes more destructive than even the most codependent partnership!
As an aside, when I presented for addiction treatment 13 years ago I told the addictionologist about my background in neurochemistry, and went on to explain that I was fairly certain that I suffered from a deficiency of natural opioids.  That doctor got a kick out of my story, and I would enjoy a sense of justification if my hypothesis someday proved to be correct.
When one considers using treating depression with buprenorphine, the obvious deal-breaker is the same issue that has prevented every other serious consideration of treating depression with opioids, namely the development of tolerance at the mu opioid receptor.  Because of tolerance, anyone who finds relief from depression with buprenorphine would be cursed by the need for eventual withdrawal, as well as other consequences of opioid dependence. I assume that Samidorphan is added to ALKS 5461 to prevent mu activation and tolerance.  Beyond partial agonist effects at the mu receptor, buprenorphine antagonizes (blocks) delta and kappa opioid receptors.  These blocking actions are not subject to tolerance, and may provide avenues for treating pain and/or depression.
Depression causes significant morbidity throughout the world, so there are huge profit incentives for new antidepressant medications. Addiction creates a large market as well, but companies rarely go as far out on a limb for addiction products as they do for other diseases. The need for new antidepressants is acute, but in an alternate universe where pain and addiction treatment take priority, Samidorphan and related opioid molecules might have a number of benefits. I’ve posted, for example, about my experience treating severe chronic pain by combining buprenorphine with an opioid agonist.  I expect the combination to be exploited eventually given the need for effective pain treatments, perhaps using an analog of Samidorphan.
Doctors use buprenorphine to treat opioid dependence.  The goal of buprenorphine treatment is to block the cycle of use and reward for some period of time, and to allow patients to create support systems, establish self-sufficiency, regain self-esteem, and practice living ‘life on life’s terms.’  The amount of time that it takes to accomplish these goals likely varies depending on the individual’s premorbid function, life experiences, insight, genetics, and other factors, but studies suggest that a year is not long enough to make meaningful headway.   It is possible that for some people, opioid dependence is a relatively permanent condition that is best controlled with life-long maintenance treatment.   But for those who would like to try to maintain sobriety off buprenorphine, the tapering process reignites the circuits that were set up by the initial addiction, causing cravings, withdrawal, and the constant obsession to delay the taper and resume the prior day’s dose of opioid.
If ALKS 33 has a long half-life and blocks buprenorphine in a dose-dependent manner, I could picture an alternate strategy for stopping buprenorphine where the antagonist (ALKS 33) is introduced to buprenorphine patients at a gradually-increasing dose.  The goal would be to eventually have the person on a daily dose of Samidorphan sufficient to block all of buprenorphine’s effects at the mu receptor, at which point the person could discontinue buprenorphine without withdrawal.  I suspect that the patient would experience withdrawal in response to each increase in dose of Samidorphan, although withdrawal would be reduced by introducing the drug at a measured pace.
What is the value in tapering in such a ‘reversed’ way?  Why would adding an antagonist be preferable to the current process, i.e. simply reducing the dose of buprenorphine over time?  The answer comes from an understanding of the nature of addiction.  A person stopping buprenorphine by gradually adding Samidorphan would face the decision once per day, whether to take the next dose of Samidorphan.  Compare that once-per-day decision to the current method of tapering buprenorphine, where the person must decide, thousands of times per day, to NOT take more buprenorphine.  I would expect that deciding to take an antagonist once per day would be more likely to succeed then CONSTANTLY deciding NOT to take buprenorphine all day long, throughout all of life’s ups and downs—times when the patient was conditioned to take opioids.
We will learn more about Alkermes new medication in coming months. I hope that someone in a power position will consider some of the other diseases that might respond to these interesting chemicals, including opioid dependence.

Uncoupling of analgesia, tolerance, and euphoria from mu-agonists using buprenorphine

I presented this topic at the Atlanta meeting of ASAM a couple weeks ago.  There are too many slides, but the historical stuff was just too fascinating to leave out.  I wanted to demonstrate,  by lining it up on the side, how time has compressed the most critical discoveries to a very short period of time.  In other words, it wasn’t until thousands of years of opium use that the general concept of endorphines and opioid receptors came along.  We can only hope that similar understandings of the biological basis of tolerance and withdrawal will be comparatively soon.
My study shows something truly fascinating– that a partial agonist seems to anchor tolerance at a lower level, still allowing for potent analgesia, but preventing euphoria and dose escalation.  I have used this combination in people with very major surgeries, that are known to be quite painful– i.e. knee and hip replacements, dental surgeries, gallbladder surgery, and median sternotomy.

Uncoupling mu receptor tolerance, analgesia, and euphoria: Modification of agonist effects using buprenorphine.