How Long Does Suboxone Stay in Your System?

The average amount of time that Suboxone (buprenorphine) stays in your system is about 111 hours. This value is highly variable, depending on individual physiology, genetics, and a number of other factors. While Suboxone can linger in your system for days, its duration of effects seems to be 24-48 hours (based on self-reported, anecdotal evidence).

Suboxone (buprenorphine) is a semi-synthetic opioid used as substitution therapy for opioid dependent individuals. Suboxone can also be used for pain management at smaller doses in opioid-naive patients (i.e., patients that don't have a high tolerance to opioids).

Why Does Suboxone Stay in Your System for so Long?

Suboxone has an average half-life of 37 hours (range 20 - 70 hours). The half-life of a drug is the amount of time it takes for 50% of the substance to be cleared from plasma and excreted. (Plasma is the colorless fluid fraction of blood). Since the mean half-life of Suboxone is about 37 hours, the predicted time frame of Suboxone clearance is as follows:

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

After a mean of 111 hours, 12.5% of the initial dose of Suboxone will remain in your system. Of course, this value is only an average across many subjects and is highly variable. The half-life of a drug also does not correspond to the duration of effects or the amount of time that Suboxone will occupy and block opioid receptors in the brain.

Factors Affecting Suboxone Clearance

Drug metabolism is influenced by age, disease, gender, pregnancy, environmental conditions, dosage, enzyme induction and inhibition, diet and hereditary or genetic factors (think pharmacogenomics).

Age

If you're very young, you're not fully metabolically competent. Fetuses have the CYP3A sub-family of hepatic enzymes only, and poor metabolism overall. The elderly also exhibit diminished drug metabolism and excretion, in addition to diminished enzyme induction. (Enzyme induction is when a drug or substance that is introduced inside your body activates or induces the expression of an enzyme, prompting your body to produce more of it).

Disease State

Since Suboxone is cleared by the liver, hepatitis and hepatic cancer will impair Suboxone drug metabolism, and can result in fatal overdose. Since Suboxone is eliminated by the liver, there is no danger for individuals with decreased kidney function (renal impairment).

Route of Administration and Dose

When high-dose Suboxone is administered intraveneously, the time it takes to be cleared from your system differs from oral administration. The average half-life for IV Suboxone is roughly 25 hours [note]Huestis MA, Cone EJ, Pirnay SO, Umbricht A, Preston KL. Intravenous buprenorphine and norbuprenorphine pharmacokinetics in humans. Drug Alcohol Depend. 2013;131(3):258-62.[/note].

One study reported the following pharmacokinetic data concerning high-dose, IV Suboxone:

Buprenorphine dose (mg) Mean intravenous Half-Life (t1/2) Cmax (ug/L)
2 21.8 +/- 3.7 21.6
4 27.5 +/- 4.9 56.3
8 28.0 +/- 3.0 110.8
12 22.3 +/- 2.6 164.5
16 25.6 +/- 1.1 174.8

Liver Enzymes

Suboxone is metabolized in the liver by the enzyme CYP3A4 , and to a lesser extent, CYP2C6. The activity of these enzymes affects the rate of Suboxone metabolism. Genetic variability influences enzymatic activity, and therefore also affects how long Suboxone will stay in your system.

Over 28 single nucleotide polymorphisms (SNPs) have been characterized in the CYP3A4 gene (that encodes the CYP3A4 liver enzyme). However, these genetic differences do not translate into significant individual variability in enzyme activity.

While over 28 single nucleotide polymorphisms (SNPs) have been identified in the gene, it has been found that this does not translate into significant interindividual variability . It can be supposed that this may be due to the induction of CYP3A4 on exposure to substrates.

Poor functioning CYP3A4 alleles include CYP3A46 (caused by an A17776 insertion), and CYP3A417 (F189S). Both of these genetic variants (polymorphisms) impair enzyme activity, decreasing metabolism of Suboxone, resulting in delayed Suboxone excretion.

CYP3A4 Enzyme Inducers and Inhibitors

CYP3A4 is also induced and inhibited by a number of ligands (drugs, supplements, etc). Induction of the enzyme hastens Suboxone removal, whereas CYP3A4 inhibitors cause Suboxone to linger in your system. Here's a list of substances that can induce or inhibit the hepatic CYP3A4 enzyme. For example, Valerian (the herb present in tea and some supplements) is a moderate CYP3A4 inhibitor, whereas St. John's Wort induces CYP3A4. Therefore, Valerian would prolong the amount of time that Suboxone stays in your system, whereas St. John's Wort would increase Suboxone elimination.

The rate of increase or decrease from CYP3A4 induction or inhibition is highly variable and depends on the substance.