Percocet is a brand name medication comprised of active ingredients oxycodone (a semi-synthetic opioid) and acetaminophen (paracetamol). It was first introduced to Germany in 1917 as an intravenous formulation for pain management among soldiers in World War I. Eventually it received approval in the United States (1976) as an oral (tablet) formulation as a narcotic analgesic for the treatment of moderate to severe acute pain.
The oxycodone within Percocet functions by acting as an agonist upon opioid receptors in the brain, primarily mu-receptors, but also kappa and delta receptors – thereby facilitating potent analgesic effects. The opioidergic effect decreases levels of cAMP (cyclic adenosine monophosphate) and elevates extracellular levels of neurotransmitters such as: acetylcholine, dopamine, GABA, norepinephrine, and substance P. This can often promote improved mood (euphoria), relaxation, and pleasure – making Percocet a popular drug of abuse.
Long-term users of Percocet often report rapid onset of tolerance, addiction, and/or dependence upon the drug for daily functioning. Furthermore, the drug may deplete the body’s endogenous endorphin production, digging users into an even deeper hole of pain when they discontinue. As a result of deleterious long-term effects, many users are kicking their Percocet habit and attempting to clear the drug from their system.
How long does Percocet stay in your system?
If you haven’t yet ceased your usage of Percocet, but want to clear it from your system, it is recommended to discontinue only under the supervision of a medical professional. On the other hand, if you’ve stopped the drug (or ran out of pills) and faced the hellacious Percocet withdrawal symptoms, you may want to know whether it is really out of your system. Since Percocet is comprised of both acetaminophen and oxycodone – it is necessary to analyze clearance times for each substance.
Most sources suggest that half-life of oxycodone within Percocet is an estimated 3.51 hours +/- 1.43 hours. This means that on average, it will take 19.31 hours to fully clear the oxycodone portion of Percocet from your system. By comparison, the half-life of the acetaminophen portion of Percocet is approximated at 3.1 hours – significantly less than oxycodone.
Assuming the half-life of acetaminophen at 3.1 hours is accurate, it will have been cleared from your system in just over 17 hours. Some sources speculate that the half-life of acetaminophen could even be shorter (at 2 hours), resulting in excretion in under 11 hours. A majority of Percocet users will have fully (100%) cleared both the oxycodone and acetaminophen ingredients from their system within 24 hours; only in rare cases would clearance be prolonged between 24 and 48 hours.
Note: Though Percocet may be eliminated from your system within 2 days, the metabolite oxymorphone may take between 1.6 and 2.06 days to be fully excreted.
- Source: http://www.ncbi.nlm.nih.gov/pubmed/3829578
- Source: https://pubchem.ncbi.nlm.nih.gov/compound/oxycodone
- Source: https://dailymed.nlm.nih.gov/dailymed/archives/fdaDrugInfo.cfm?archiveid=17971
Factors that influence how long Percocet stays in your system
There are several factors that may influence how long Percocet (oxycodone/acetaminophen) stays in your system. Examples of such factors include: the individual (age/genetics/health), whether taken with other drugs, the frequency of Percocet ingestion, and the dosage administered.
An array of individual factors should be taken into account when considering how long Percocet will remain in a person’s system. These include things like: a person’s age, their body mass index, food/water consumption, their health (specifically related to liver/kidney function), metabolic rate, and their urinary pH.
Age: Elderly individuals (ages 65+) aren’t able to efficiently metabolize and excrete drugs like younger people. Though the reason isn’t well understood, it is believed that organs such as the liver and/or kidneys aren’t functioning as well in the elderly compared to younger individuals. Specifically, it has been theorized that reduced blood flow to the liver may contribute to poorer metabolism and longer retention times of Percocet. In addition, elderly patients often have other health problems and may be taking medications that impair metabolism and drug excretion.
Body height/weight/fat: A person’s height, weight, and body fat percentage may also influence the rate at which Percocet (oxycodone/acetaminophen) are cleared from the body. Generally, the greater the dose of Percocet that a person takes in respect to their height and weight, the longer the drug will be retained. In other words, a short/lightweight person taking 10 mg Percocet will likely take slightly longer to excrete the drug than a tall/heavyweight individual. Also, the greater a person’s body fat percentage, the quicker the excretion rate.
Genetics: It could be hypothesized that genetic variation may facilitate either enhanced or reduced metabolism and clearance of Percocet. Since the drug is metabolized by CYP450 (cytochrome P450) within the liver (mostly CYP2D6), genes regulating these enzymes could affect clearance rates. As a result, some individuals may metabolize Percocet at faster-than-average rates (possibly resulting in quicker excretion), whereas others may be poor metabolizers of Percocet (possibly resulting in slower excretion).
Glutathione levels: It is known that acetaminophen is metabolized by CYP450 within the liver, yielding a toxic metabolite. This toxic metabolite (NAPQI) is detoxified upon conjugation with glutathione. Frequent ingestion of acetaminophen (within Percocet) could deplete glutathione levels, leading to prolonged metabolism and clearance. Those with high glutathione stores (usually younger individuals) may clear acetaminophen faster than those with low levels.
Food intake / Hydration: Whether Percocet is taken with food or on an empty stomach could influence absorption, metabolism, and excretion. The extent to which pharmacodynamics of Percocet are affected by food ingestion and amount of water consumed remain unclear. However, someone who takes Percocet on a full stomach may compromise its absorption. Furthermore, certain foods/drinks (e.g. grapefruit juice) can reduce first-pass metabolism, possibly prolonging clearance.
Liver/kidney function: Percocet is metabolized extensively by enzymes in the liver. Should an individual have taken the drug with hepatic impairment – the metabolism of the drug may be prolonged, resulting in extended clearance times. Some studies have shown that the half-life of oxycodone within Percocet could be increased by up to 2.3 hours among those with mild/moderate hepatic impairment. Among those with renal impairment, half-life is increased by up to 1 hour. This means that individuals with both hepatic and renal impairment may take over 1.56 days to fully clear the drug from their system.
Metabolic rate: A person’s basal metabolic rate (BMR) may influence the speed at which an individual metabolizes and excretes Percocet. Usually the greater a person’s BMR, the quicker exogenous substances like Percocet are broken down and eliminated from the body. Though genetics certainly influence metabolic rate, a person’s dietary intake and exercise habits also play a role.
Urinary pH: The majority of Percocet is excreted from the body via urine, but excretion could be influenced by a person’s urinary pH. Usually the greater the alkalinity of a person’s urine, the slower the drug clearance. Urine of high alkalinity can facilitate reabsorption of Percocet, elongating the clearance period. On the other hand, individuals with highly acidic urine tend to excrete Percocet at the fastest possible rate after it is metabolized.
Taking other drugs (Inducers vs. Inhibitors)
If you are taking other drugs along with Percocet, it is necessary to consider that they may have significant affect upon clearance times. Since the oxycodone portion of Percocet is metabolized via CYP2D6 isoenzymes in the liver, drugs that alter functioning of CYP2D6 will influence clearance rates. Certain drugs known as CYP2D6 “inducers” are known to expedite the metabolism of drugs like Percocet, possibly speeding up systemic clearance.
Examples of such CYP2D6 inducers include: Dexamethasone and Rifampin. Due to the fact that only a select few drugs actually “induce” activity of CYP2D6, the chances of you taking one along with Percocet are slim. What’s more likely is that you’d be taking a drug classified as a CYP2D6 “inhibitor.” These drugs interfere with CYP2D6 metabolism of Percocet and extend total clearance times.
Some examples of CYP2D6 inhibiting agents include: Amiodarone, Celecoxib, Codeine, Yohimbine, and SSRIs. Keep in mind that certain substances have a greater “inhibiting” and/or “inducing” effect than others – and this effect may be dose-related. If you are unsure as to whether a specific drug could be an inhibitor or inducer, talk to your doctor.
Frequency of ingestion
Another factor to consider when estimating Percocet clearance is how often a person takes the drug. Someone who takes Percocet several times per day (on a daily basis) will likely have accumulated a greater amount of the drug in their system compared to someone who takes Percocet once a week (once per day). It is thought that frequent ingestion of Percocet over a period of several days will yield peak levels of accumulation within a person’s body.
On the other hand, infrequent ingestion of Percocet (e.g. single-dose) are unlikely to reach peak levels of accumulation. Furthermore, it is also important to consider that multi-dose users often ingest their last dose of Percocet later in the day than single-dose users. Taking a dose later in the day may prolong clearance due to the fact that sleep slows metabolism and physiological functions.
It may also be true that the total duration over which a person has been taking Percocet may trigger physiological adaptations that alter clearance rates. For example, it could be speculated that over time, a toll may be taken on the liver and/or kidneys – thereby prolonging clearance rates. If theory is true, infrequent users of Percocet may metabolize the drug more efficiently, resulting in faster excretion.
It is thought that the greater the daily dosage of Percocet ingested, the slower the clearance times. On the other hand, those that take a very small dosage may have quicker clearance times. While dosage in proportion to a person’s body size (height/weight) may impact clearance, total dosage ingested may as well.
Larger quantities of ingested Percocet will be of greater burden to the liver and kidneys compared to smaller doses. Furthermore, physiological adaptations that slow clearance may also be more likely when high doses are taken. Percocet is formatted in a variety of dosing options with blends of oxycodone/acetaminophen including: Percocet 2.5/325 mg, Percocet 5/325 mg, Percocet 7.5/325 mg, Percocet 10/325 mg, and Percocet 10/650 mg.
There are different dosing instructions based on the specific blend prescribed. Smaller doses such as the 2.5/325 mg and 5/325 mg are not to be taken more than 12 times per day. Moderate doses of 7.5/325 mg and 7.5/500 mg are not to be taken more than 8 times per day. Large doses of 10/325 mg and 10/650 mg aren’t meant to be taken more than 6 times per day.
Percocet tablets come in six different doses. Percocet 2.5/325 mg and 5/325 mg should be taken no more than 12 times a day. Tablets of 7.5/325 mg and 7.5/500 mg can be taken up to 8 times per day. The maximum dosage for Percocet 10/325 mg and 10/650 mg is 6 tablets per day. Someone taking the highest dosage (10/650 mg) at the highest frequency (6x per day) will excrete the drug at a slower rate than a person taking the lowest dose (2.5/325 mg) infrequently (e.g. once per day).
- Source: https://pubchem.ncbi.nlm.nih.gov/compound/oxycodone
- Source: http://www.ncbi.nlm.nih.gov/pubmed/20406214
- Source: http://www.ncbi.nlm.nih.gov/pubmed/11831542
- Source: http://www.ncbi.nlm.nih.gov/pubmed/3829578
How Percocet is Absorbed, Metabolized, and Excreted (Details)
Upon ingestion of Percocet, both the oxycodone and acetaminophen are rapidly absorbed by the gastrointestinal tract (through the lining of the small intestine). Peak blood levels of the oxycodone portion are attained within approximately 1 hour of ingestion. An analgesic effect is typically experienced within 15 minutes, peaks within 60 minutes, and is maintained for an estimated 4 to 6 hours.
Between 60% and 87% of the oxycodone is thought to reach systemic circulation following a single oral dose. First-pass metabolism of oxycodone facilitates N-demethylation (via CYP3A4/CYP3A5) to noroxycodone, whereas O-demethylation (via CYP2D6) facilitates oxymorphone. The isoenzyme CYP2D6 (within the liver) is thought to play the biggest role in the breakdown of oxycodone into metabolites: noroxycodone (free and conjugated), oxycodone (free and conjugated), and oxymorphone.
The kidneys are chiefly responsible for excretion of these oxycodone metabolites. Estimates suggest between 8% and 14% of a standard dose is excreted as free oxycodone within 24 hours of administration. Both noroxycodone and oxymorphone are thought to have longer half-lives compared to oxycodone – hence being detectable for a longer duration in urine.
Quantities of metabolites present in urine include: 19% oxycodone, 50% conjugated oxycodone, 14% conjugated oxymorphone, along with minimal amounts of noroxycodone. The acetaminophen portion of Percocet is circulated evenly throughout bodily fluids and metabolized by CYP450 (cytochrome P450). An estimated 85% of acetaminophen is conjugated with glucuronic acid, as well as sulfuric acid and cysteine.
Following acetaminophen conjugation within the liver, over 90% is usually excreted via urine within 24 hours. The average half-life for Percocet (oxycodone/acetaminophen) is 3.51 hours +/- 1.43 hours. Since the oxycodone has a longer half-life than acetaminophen, it is the oxycodone that takes longer to excrete from the body.
Oxycodone and its metabolites are excreted primarily via the kidney. On average, Percocet is fully cleared from a person’s system within 20 hours at a clearance rate of 0.8 liters per minute in adults. However, it should be considered that the “oxymorphone” metabolite may take over 2 days to completely excrete.
- Source: https://pubchem.ncbi.nlm.nih.gov/compound/oxycodone
Types of Percocet Drug Tests
There are many types of drug tests that could be utilized to determine whether someone has ingested Percocet. Since the acetaminophen portion of Percocet isn’t regarded as problematic, most drug tests will determine whether an individual has ingested oxycodone – the opioidergic component. Oxycodone may be detected through a variety of testing modalities including: urine samples, blood samples, hair samples, and oral fluid (saliva) samples.
Urine tests: Percocet is usually detectable in urine samples within just 2 hours of ingestion and for up to 48 hours after a single administration. Peak concentrations of both oxycodone and its metabolites will appear in urine between 3 hours and 19 hours post-administration. Since levels of oxycodone are highest in urine, both free-form and conjugated oxycodone are easiest to detect.
However, the oxycodone metabolite “oxymorphone” has a longer half-life, and therefore can be detected for a longer duration – especially among frequent users. Some research has shown that oxymorphone remains detectable for approximately 10 hours longer than oxycodone in urine. Cutoff concentrations of oxycodone and metabolites on a urinalysis is generally set at 50 ng/mL; anything over this level is considered “positive.”
Due to convenience and lack of invasiveness, urine samples are the most popular way to test for oxycodone ingestion. Furthermore, urine tests can detect oxycodone for a longer duration compared to blood tests and/or saliva tests. Results of a urine test can then be confirmed with GC/MS, ELISA, and EIA.
Blood tests: The oxycodone component of Percocet is known to peak in the bloodstream within 1 hour of ingestion. It is likely that Percocet would first become detectable via a blood sample within 15 to 20 minutes of ingestion and remain detectable for up to 24 hours post-ingestion. Due to the fact that the drug isn’t detectable for as long of a duration in a blood sample compared to urine sample, blood tests are seldom utilized.
Blood tests are beneficial when urine samples cannot be taken due to the fact that a person is unconscious and/or hospitalized. In this case, a blood draw will reveal whether oxycodone/acetaminophen is present. Information from a blood analysis can then be used to properly treat an overdose.
Hair tests: Another way to test for the presence of Percocet (specifically oxycodone) is via a hair sample. Should you partake in a hair-based drug test, approximately 20 to 50 hair follicles may be collected from the top of your head and sent to a laboratory for an analysis. Most follicles will need to be at least 3 cm (in length) for accurate results.
Though hair tests are capable of detecting the presence of oxycodone (and its metabolites) for up to 30 days (1 month) post-ingestion, results aren’t always accurate. At a cutoff level of 100 pg/mg, it is extremely difficult to detect oxycodone, oxymorphone, and noroxycodone in human hair. Hair tests are most likely to detect oxycodone in chronic/high-dose uses, but may not justify the costs among infrequent/low-dose users.
Saliva tests: The oxycodone within Percocet can be detected in an oral fluid (saliva) sample. Saliva tests are considered advantageous over hair tests due to the fact that they are non-invasive and often yield quick results. Furthermore, oxycodone concentrations within saliva are most closely related to blood levels (compared to concentrations within urine).
Saliva tests are generally administered by law enforcement agents when they suspect an individual may be intoxicated. Following collection of a saliva sample, the saliva can often be applied to a device for nearly-instantaneous feedback regarding whether oxycodone was ingested. An additional sample can be collected and sent to a laboratory for more advanced analysis to verify whether an individual had ingested oxycodone.
- Source: http://www.ncbi.nlm.nih.gov/pubmed/20109300
- Source: http://www.ncbi.nlm.nih.gov/pubmed/7536861
- Source: http://www.ncbi.nlm.nih.gov/pubmed/23609023
- Source: http://www.ncbi.nlm.nih.gov/pubmed/14516487
- Source: http://www.ncbi.nlm.nih.gov/pubmed/22798176
Who could be tested for Percocet?
There are a variety of individuals that could be subject to extensive drug tests, capable of detecting oxycodone ingestion. Standard drug tests such as the SAMHSA-5 will not assess for prescription oxycodone ingestion. Individuals that may be subject to more comprehensive drug testing include: athletes, employees, rehabilitation patients, and military members.
- Athletes: Though prescription opioids are not considered a part of standard drug testing among professional and collegiate athletes, randomized extensive screenings may be administered. These extensive screenings may be capable of detecting ingestion of oxycodone, which could signify that a semi-synthetic opioid (e.g. Percocet) was taken. When taken without medical consent, an athlete may be suspended, banned, or face legal ramifications.
- Drug rehab patients: In rehabilitation, it is often difficult for patients to remain sober. As a result, drug rehabilitation facilities may require extensive drug assessments – capable of detecting prescription drugs. Should an individual in rehab test positive for oxycodone (or its metabolites), they may need to spend more time in rehab and/or face a penalty.
- Employees: Though most employers only test for illicit non-prescription drugs, some are starting to test for ingestion of prescription agents – especially those that depress the CNS and ultimately impair motor skills. Percocet is an example of a CNS depressant that could compromise on-the-job performance, leading to increased errors and/or decreased productivity. Errors in a job requiring attention to detail (e.g. operating machines) could result in injuries, deaths, and/or equipment damage. For this reason, individuals caught working after taking oxycodone may be fired.
- Military personnel: In the military, attention to detail and peak levels of alertness are crucial. One mistake in combat could lead to an unnecessary death and/or injury. Therefore military personnel typically avoid using CNS depressants and opioidergic medications. Extensive drug testing to detect oxycodone may be administered on occasion to troops. Should an individual test positive for oxycodone without medical consent, he/she may be delisted without compensation.
Tips to clear Percocet from your system
If you’ve taken your last dose of Percocet and want to clear it from your system as quickly as possible, you may want to implement some clearance strategies. Understand that while these strategies may not significantly improve metabolism and clearance times, they could have a subtle impact. Should you consider any of the clearance strategies listed below – always verify safety with a medical professional before taking action.
- Stop taking it: Some Percocet users think that after they’ve stopped for awhile, they can take the drug on an “as needed” basis and it won’t accumulate in their system. Though clearance may be quicker after a “single ingestion” compared to multiple, any ingestion after discontinuation will prolong clearance. Really the only way to ensure that Percocet will have been completely excreted from your body is to stop taking it for good.
- CYP2D6 inducers: Various agents that “induce” activity of CYP2D6 enzymes can facilitate quicker metabolism and excretion of Percocet. Though these “inducers” shouldn’t be taken on a whim to expedite clearance, if you are already taking one (under medical supervision), you may clear Percocet quicker than someone who isn’t. Understand that certain CYP2D6 inducers are likely more effective than others for improving clearance times; contraindications of these inducers should always be professionally evaluated.
- Acidify urinary pH: It is well-documented that urinary pH (acidity vs. alkalinity) can impact the clearance times of various drugs. The greater the alkalinity of a Percocet user’s urine, the more likely they are to retain the drug for a longer duration and/or inhibit efficient excretion. To ensure that Percocet is excreted at the fastest possible rate, increasing acidity of urinary pH may be of benefit.
- Hydration and Diet: Sufficient hydration is necessary for clearance of most drugs. If you are dehydrated, it could affect your body’s ability to excrete Percocet via urine – slowing the process. While drinking a lot of water probably won’t speed up clearance times, staying hydrated will ensure that the drug is cleared in an optimal time. Furthermore, eating a healthy diet may be of benefit, giving your body nutrients and antioxidants to operate efficiently – thus helping with excretion.
- Regular exercise: Though exercising like a madman (e.g. running sprints in attempt to “sweat” the drug out) won’t do you much good, it is thought that exercise may be beneficial for detoxification. Getting some light exercise can help a person cope with Percocet discontinuation effects, and improve blood circulation. The improved circulation, blood flow, and metabolic benefits derived from exercise may slightly reduce excretion time.
Have you been drug tested for Percocet?
If you’ve been drug tested for prescription opioids like Percocet, share details in the comments section below. Discuss the type of drug test that was administered (e.g. urine testing) and whether you passed (tested “negative”) or failed (tested “positive”) the screening. To help others understand your situation, mention how long prior to the drug test you had stopped using Percocet.
If you passed the test, share any tips or tricks that you believe may have helped clear the drug from your system at a quicker rate. If you failed the test, had you stopped using Percocet for over 24 hours prior to testing? Though the chances of being tested for a prescription opioid like Percocet on a drug test are low, even if you’ve been using the drug consistently, the drug should be fully clear from your system within 1-2 days.