How Long Does Suboxone Block Opiates?

In this article, I'm going to discuss the timeframe of Suboxone opioid receptor blockade.

How long does suboxone block the effect of opiates? Suboxone blocks opiates for approximately 110 hours +/- 30 hours. Hence, clinically meaningful suboxone receptor blockade will occur for 80 to 150 hours.

The high degree of imprecision reflects the large range of Suboxone's half-life. This range is 20-70 hours, with a mean time of 37 hours.

The half-life of a drug is the amount of time it takes for half of the drug to be eliminated from your body (or technically, for plasma concentrations to be reduced to 50% of the initial value).

Since the average half-life of Suboxone is ~37 hours, we obtain the following timescale for Suboxone clearance:

Time After Dosing Suboxone Remaining
37 hours 50%
74 hours 25%
111 hours 12.5%

After ~111 hours, 12.5% of the initial dose of Suboxone will remain. Of course, this value is subject to extreme variability due to a number of factors.

Factors Affecting Suboxone Clearance

Buprenorphine (Suboxone) is metabolized by liver enzymes. Specifically, the hepatic CYP3A4 enzyme converts buprenorphine into norbuprenorphine. There are genetic differences in the activity of this enzyme that affect the elimination half-life of Suboxone.

The metabolite norbuprenorphine is biologically active and binds to and activates opioid receptors (unlike Buprenorphine which blocks them). However, buprenorphine has very poor brain penetration which limits its effects in the brain.

Because is buprenorphine (Suboxone) is metabolized by the hepatic CYP3A4 enzyme, a number of CYP3A4 inhibitors and inducers can effect the length of time that Suboxone blocks opiates. For example, St. John's Wart, Modafinil and Quercetin are all CYP3A4 inducers which would increase CYP3A4 expression and hasten the elimination of Suboxone.