I recently accepted a young man as a patient who was addicted to hydrocodone (the opioid in Vicodin), prompting a discussion about treatment options for someone who hasn’t been using very long, and who hasn’t pushed his tolerance all that high. Perhaps it will be informative to share my thought process when recommending or planning treatment in such cases. In part one I’ll provide some background, and in a couple days I’ll follow up with a few more thoughts on the topic.
Most people who have struggled with opioids learn to pay attention to their tolerance level—i.e. the amount of opioid that must be taken each day to avoid withdrawal or to cause euphoria (the latter about 30% more than the former). For someone addicted to opioids, the goal is to have a tolerance of ‘zero’—meaning that there is no withdrawal, even if the person takes nothing. That zero tolerance level serves as a goal, making having a high tolerance a bad thing, and pushing tolerance lower a good thing.
Tolerance is sometimes used as part of the equation when determining the severity of one’s addiction. But looking at tolerance alone can be misleading. Tolerance is a consequence of heavy use of opioids, and also a cause of heavy use of opioids. Tolerance usually goes up over time, so having a high tolerance probably correlates with length of addiction in some—- but not all— cases. Tolerance is also strongly related to drug availability. A person with a severe addiction, who only has access to codeine, will likely have a lower tolerance than a person with a more mild addiction, who has free access to fentanyl, oxycodone, and heroin.
I think it is more appropriate to measure the ‘severity of addiction’ by the degree of mental obsession that the patient has for opioids. Tolerance is one piece of information in determining that obsession, but tolerance alone can be misleading.
To get a sense of the obsession for opioids, I look at many factors. Has the person committed crimes to obtain the substance? Violent crimes? What has the person given up for his addiction? Has he been through treatment? How many times? How long did he stay clean after treatment? Have his parents or spouse thrown him out of the house, and if so, does he still use? Did he choose opioids over his career? Over his kids?
Answers to these questions provide a broad understanding about the addicted person’s relationship with the substance—an understanding that is necessary when considering the likely success or failure of one treatment or another. It is also important to consider the person’s place in the addictive cycle—i.e. early, likely in denial, cocky, with limited insight– or late, after many losses, more desperate—and perhaps more accepting of treatment.
I am a fan of buprenorphine as a long-term treatment for opioid dependence, as readers of this column know. I consider opioid dependence to be a chronic, potentially-fatal illness that deserves chronic, life-sustaining treatment— and buprenorphine, in my experience, is a very effective treatment in motivated patients. But tolerance becomes a factor, when considering buprenorphine for THIS patient.
Buprenorphine has a ‘cap’ or ‘ceiling effect’ that allows the medication to trick the brain out of craving opioids. In short, as the blood or brain concentration of buprenorphine drops between doses, the opioid effect remains constant, as long as the concentration is above the ceiling level. In order to achieve the anti-craving effects of buprenorphine, the dose must be high enough to create ‘ceiling level’ effects. If buprenorphine is prescribed in lower amounts—say microgram doses— the effect is identical to the effects of an agonist, since the dose/response curve is linear at lower levels.
Buprenorphine is a very potent opioid, and the effects of the medication are quite strong at the ceiling level. Comparisons to other opioids will vary in different individuals, but in general, a person on an appropriate dosage of buprenorphine develops a tolerance equivalent to that of a person taking 40 mg of methadone per day, or approximately 60-100 mg of oxycodone per day.
A person taking even a dozen Vicodin per day has a much lower tolerance to opioids. Such a person who starts buprenorphine treatment will obtain a very significant opioid effect from the drug— unless the dose of buprenorphine is raised very slowly over a number of days. And in that case, the person’s tolerance level would be pushed much higher.
So if our current patient starts buprenorphine, he will have a much higher opioid tolerance if/when the buprenorphine is eventually discontinued. I receive emails now and then from patients who are angry at their doctor for starting buprenorphine, feeling trapped by the considerable threat of withdrawal from stopping the drug. But at the same time, taking hydrocodone and acetaminophen in high amounts creates the risk of liver damage from the acetaminophen, as well as the considerable risks from opioid dependence.
And so the dilemma. Should buprenorphine be considered in such a case?