Buprenorphine and the Liver

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When buprenorphine was approved for office-based treatment of opioid addiction in the U.S, doctors worried about possible liver toxicity. We’d seen case reports of acute liver necrosis (death of liver tissue) in patients with Hepatitis C who injected buprenorphine illicitly. So was this damage due to the drug itself, from intravenous use of the sublingual product, or from buprenorphine interaction with Hepatitis C? Until we had more information, experts recommended checking liver function tests before starting buprenorphine and periodically during treatment to monitor for liver damage.

Fortunately, further studies show no liver damage in patients prescribed buprenorphine.

In 2012, Saxon et al followed over 700 patients on buprenorphine or methadone over 24 weeks, and checked their liver function tests periodically, looking for elevations that would indicate liver inflammation or damage. Neither patients on methadone or patients on buprenorphine had significant increase in their liver function test levels, leading the study’s authors to conclude that neither methadone or buprenorphine cause liver damage. Patients with Hep C who were in this study did have elevated liver enzymes, but did not get worse over the twenty-four months while taking either medication.

In the November/December, 2014, issue of American Journal on Addictions, a new study by Soyka et. al. found the same thing. This study looked at 181 patients on buprenorphine/naloxone and followed their liver enzymes for over a year. Thirty-six percent of these patients had Hepatitis C, a group who may be at increased risk for liver damage due to drugs and medications. Liver tests were done at baseline, then at 12 and 24 weeks, and at the end of the first year at 52 weeks. One to two percent of these patients showed mild elevation of liver tests but none had evidence of drug induced liver injury.

This latest study adds to the medical literature that shows buprenorphine isn’t damaging to the liver, even in patients with Hepatitis C, in patients who take the medication as intended. (For obvious reasons, no one would ever do a study asking patients to inject the sublingual form of buprenorphine, since the medication isn’t sterile and the study would put test subjects at risk for all sorts of complications.)

So do we still need to check liver function tests for patients on buprenorphine? Most of the published guidelines about how to prescribe buprenorphine in an office setting still recommend checking liver function tests, but this data from Saxon study and the Soyka study seem to indicate this isn’t a particularly helpful thing to do.

About half of my buprenorphine patients have no insurance. After reading these studies, I’ve decided not to ask my patients to get routine liver function tests. I still think they need screening for Hepatitis C. Some doctors would say liver function tests can suggest Hep C if they are elevated, but since it’s possible to have Hep C and normal liver function tests, I think their money would be better spent on Hep C testing. Patients who test positive would then need to get further testing, which would likely include liver function tests, as well as confirmatory testing for Hep C.

Let’s use new information to spend health care dollars wisely.

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One response to this post.

  1. Posted by Alan Wartenberg on November 23, 2014 at 10:30 pm

    My only concern would be the several studies out there that show that people with more advanced hep C may get oversedated on lower doses of buprenorphine, so I strongly encourage my patients to get tested. I had tried, while I was employed by this one particular program, to get them to foot the bill for EVERY patient for hep C testing as part of the initial (and then annual) testing, but since it was not required they would not. Strictly speaking, it doesn’t necessarily make a difference, since we are always looking for signs/symptoms of oversedation, but knowing patients’ hep C status in advance could alert us to the need of more frequent and careful monitoring (including seeing people at peak levels of buprenorphine, as we often do with methadone).

    Reply

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