Duffy asked
I’m prescribed 10mg of oxycodone 3 times daily. I took 25mg this morning at 6 a.m. and another 10mg at noon. It was the last of my medicine and I was starting to feel withdrawal symptoms so I took around 1mg of some Subutex I had left over from when I was on them. Now I have rapid bowel movements and awful anxiety. I think I put myself into precipitated withdrawal. Am I in any danger? Also I read the way to stop it is to take more buprenorphine.
Answer
Subutex (buprenorphine) is well known to precipitate withdrawal in individuals that are currently dependent on opioid agonists, such as hydrocodone or oxycodone. Per the prescribing information for Subutex:
"Because of the partial agonist properties of buprenorphine, SUBUTEX sublingual tablet may precipitate opioid withdrawal signs and symptoms in individuals physically dependent on full opioid agonists if administered sublingually or parenterally before the agonist effects of other opioids have subsided."
Below, we describe how buprenorphine can cause withdrawal.
How Can Buprenorphine Cause Withdrawal?
Buprenorphine is a mixed agonist-antagonist narcotic. It works as a:
- Partial agonist at the mu-opioid receptor
- Antagonist at the kappa-opioid receptor
- Agonist at the delta-opioid receptor
How buprenorphine can cause withdrawal can be a confusing subject, especially since it does act in a similar manner as traditional opioid analgesics, such as oxycodone, in some respects.
Opioids that are indicated for the treatment of pain, including oxycodone, hydromorphone, morphine, hydrocodone and fentanyl, work primarily as mu-receptor agonists. Agonizing the mu-receptor creates many of the effects we associate with opioids, such as:
- Pain relief (analgesia)
- Euphoria
Mu-receptor agonism also creates many of the side effects of opioids, such as:
- Respiratory depression
- Miosis (pupil constriction)
- Constipation
- Physical dependence
Although buprenorphine acts like oxycodone in the sense that it also binds to and agonizes mu-receptors, it is not nearly as potent (i.e. has less activity) as other opioid agonists but, and this is a key point, it binds much more strongly to the receptors.
Essentially, if an individual takes buprenorphine soon after another opioid agonist, such as oxycodone, it will displace that opioid, bind more strongly to the receptor, but have less activity. Blockade of the effects of full mu-receptor agonists like oxycodone occurs soon after administration of buprenorphine.
Another way to put this is that buprenorphine "blocks" other opioid drugs from binding to the mu receptor. Since buprenorphine has relatively low activity on the opioid receptor, it doesn't typically produce the high degree of analgesia that other opioids do. This can be a huge problem for someone dependent on opioids. The lower activity of buprenorphine will be the cause of the withdrawal symptoms.
Adding to the problem is that buprenorphine binds to the mu-receptors for a long time, with some sources stating that it is over 24 hours. Even if you take a mu-receptor agonist, like oxycodone after buprenorphine, it will have little effect since the receptors are already occupied by buprenorphine.
In terms of taking more buprenorphine to help with withdrawal symptoms, it may help, but you should speak with your doctor first before doing so. Effective doses range from 4mg all the way up to 24mg. However, depending on your medical history, it could make the problem worse.
What Are Withdrawal Symptoms From Opioids?
Potential withdrawal symptoms from opioids include:
- Flu-like symptoms
- Insomnia
- Anxiety
- Abdominal cramps and other GI symptoms
- Fatigue
Most withdrawal symptoms are mild to moderate in severity, but can certainly be a challenge, depending on how long you were taking other opioids. Severe side effects, like an enhanced feeling of pain, aren't overly common, but it can happen.
Not only can abrupt withdrawal from opioids cause these side effects, taking other medications (like buprenorphine) can as well. It is important to never take medication that has not been prescribed to you or is no longer a currently active therapy for you. Be sure to speak to the doctor about the effects you are experiencing.
