Opana is the brand name for oxymorphone, an opioid that is manufactured and distributed for the treatment of moderate to severe levels of pain. Opana is known for being twice as strong as OxyContin, itself a strong painkilling opioid. As a result, Opana’s potency has raised many questions about its use and effects on the human body, including how long oxymorphone stays in a person’s system after it has been consumed.
The Half-Life of a Drug
The length of time a drug stays in the body is known as the duration of action, which is expressed as a numerical value known as a half-life. A half-life is the period of time required for the amount (or concentration) of the drug in the body to decrease by one-half. This is determined by the amount of the drug in plasma, the clear, liquid portion of blood that remains after red and white blood cells, platelets, and other components are extracted. Plasma is the single largest component of human blood (comprising approximately 55 percent of what makes up blood), which is why a drug’s plasma half-life is based on how quickly the drug is eliminated from the plasma.
When a drug molecule leaves plasma, a number of things can happen to it; it can be removed from the body, it can be sent to various other tissues in the body, or it can be broken down in the bloodstream. Both the removal of a drug and the transfer of the drug to another body tissue determine the half-life of a drug – precisely how long it takes for the amount of the drug in the body to go down by one-half.
When it comes to Opana, the half-life of oxymorphone depends on how the drug is administered: either its extended-release (ER) form or its immediate-release (IR) form. As Opana ER, oxymorphone’s half-life is 9-11 hours; that is, it takes around 10 hours for the amount of oxymorphone in the person’s system to decrease by 50 percent. The oxymorphone that is delivered in Opana ER reaches peak concentration about three hours after consumption. The Opana IR format has a half-life of 7.3-9.4 hours, and oxymorphone reaches peak concentration in the body just 30 minutes after it is taken.
Extrapolating the hours, Mental Health Daily estimates that it could take up to 2.5 days for Opana ER to be completely eliminated from the body, and a little more than two days for Opana IR to be worked out of the body’s system. Three days would be a safe bet for complete removal from the last Opana dosage, regardless of the formulation.
Individual Factors Explaining Elimination
It would be possible for many people to take 20 mg of Opana ER at the same time, but one person is more likely to eliminate the drug sooner than the other users. In a situation like this, neither the dosage, the Opana format, nor the time of administration explain the difference in half-life elimination. If these factors are removed from the equation, then individual factors, like age, body mass, genetics, the presence of other drugs, and food intake, also have a role to play in determining the how long Opana stays in a user’s system.
With age, for example, how old a particular Opana user is can have a say in how long oxymorphone remains in the body after its consumption is stopped. The Consultant Pharmacist journal writes of how people over the age of 65 have poorer kidney and liver systems, both of which can affect how drugs move through the body; having kidneys and livers that work more slowly means that Opana’s half-life is increased, and the drug stays in the body longer. Furthermore, elderly people tend to be on additional medications and have other health issues, which can prolong the amount of time it takes for Opana to work its way through their systems.
Consuming alcohol with Opana changes the proportion of the oxymorphone that enters circulation, and therefore changes the effect of the drug and how long it remains in the body. Depending on the individual user, alcohol increases the peak plasma concentrations of Opana to anywhere between 70 percent and 270 percent. The stronger the alcohol, the higher the plasma concentrations of Opana.
Taking alcohol with prescription medication is extremely dangerous. If a user drinks alcohol and takes Opana, the plasma concentrations of the oxymorphone will be much higher than they should be, which increases the half-life of the drug in the body.
Body Mass and Food Intake
Body mass and fat percentage (the total mass of fat, divided by total body mass) also determine the length of time Opana remains in the system. For people who have a high percentage of body fat, it may take longer to achieve stable concentrations of oxymorphone. Such people tend to have more fat stores that the Opana can accumulate in, so it may take longer for the drug to be eliminated. Research of patients who are both obese and non-obese has found that people with a high percentage of body fat have different rates of drug distribution, elimination, and clearance within their bodies. The journal Clinical Pharmacokinetics suggested that for such people, Opana would remain in their systems for more time than usual even after consumption of the drug had been discontinued.
Much research has suggested that food intake also affects how much oxymorphone enters into circulation when introduced to the body (a process known as bioavailability). For Opana’s extended-release formulation, food intake prior to ingestion increased the maximum concentrations of the oxymorphone released, as opposed to in those who took the drug without having consumed any food for a set period of time beforehand.
As an example, people who fasted before having a single 40 mg dose of Opana ER had peak plasma concentrations of 2.8 ng/ml (nanogram/milliliter) within 60 minutes of consumption. People who ate before they took 40 mg of Opana ER reached their peak plasma concentrations of 4.25 ng/ml two hours after consumption.
Research from the Food and Drug Administration suggests that consuming food immediately before taking Opana ER can extend the time that the oxymorphone in the dose remains in the circulation. A patient who eats a large meal before taking the prescribed Opana ER dose could have to wait for a long period of time for the oxymorphone to be eliminated from the plasma compared to a patient who took the medication on an empty stomach.
Having a weak liver may also affect Opana’s bioavailability after consumption. People who have hepatic impairment (some form of liver failure) have demonstrated a bioavailability of 1.6 times those who have normal hepatic (liver) functionality. In cases of acute liver failure, Opana stays in the system 12.2 times longer.
While there is no significant evidence that would suggest liver impairment increases the elimination half-life of Opana, people who have livers that are functioning under par could be at an increased risk of Opana having a longer half-life in their bodies. For people who are older, who have alcoholic liver cirrhosis, or who have a family history of liver problems, their hepatic impairment will have a minor influence on how long it takes for their bodies to process Opana, but hepatic weakness does not seem to be a major factor.
The rate at which metabolism (the chemical processes that take place within the body) occurs is believed to affect the speed at which a drug is broken down and removed from the body. The higher a person’s basal metabolic rate, the faster that person’s body will use Opana. On the other hand, a lower metabolic rate means that Opana has to stay in the system longer before it can be eliminated. Metabolic rate does not have much influence over the processing of Opana; the role it plays is a minor one, but it could be important if it exists in combination with other factors.
With the renal (kidney) system, however, there is a greater likelihood that how well that system works has an effect on how long Opana stays in a particular person’s system. The kidneys are responsible for excreting a majority of the Opana dosage, and studies have found evidence that people who have impaired renal function have an accumulation of substances (known as metabolites) that are formed via the process of metabolism (that is, having weak kidneys prevents the body from fully eliminating all traces of oxymorphone after it has been broken down).
In fact, the accumulation of those substances might cause them to be reabsorbed by the body and then recirculated through the system. Researchers in the Palliative Medicine journal wrote that it is very possible that a patient who has severe renal impairment (kidney failure) would show an increase in the elimination half-life of Opana ER (even a modest increase). The elimination half-life is more likely to go up proportionally to how badly the kidney function has been compromised; the weaker the kidneys (and their ability to remove waste products from the body), the greater the accumulation of metabolites, and the longer it takes for oxymorphone to be fully expunged.
Dosage and Frequency of Administration
Dosage and frequency of administration will also affect how long Opana stays in the system. Typically, the less Opana consumed, the faster the body will eliminate it from plasma circulation. Since Opana ER has a 10-hour half-life, taking a 40 mg dose would lead to 20 mg within the plasma 10 hours after consumption, and a 10 mg dose would be reduced to 5 mg in plasma in the same time period. Patients who take low doses of Opana would have less oxymorphone in their systems to begin with, meaning that the concentration of oxymorphone in their plasma would be considerably, and much more quickly, broken down than in patients who took higher doses.
Patients who take higher doses of Opana may be subject to inefficient renal excretion because there are more metabolites that have to be removed. The metabolites could accumulate within the renal system and fat stores, which would result in the elimination process being elongated. Taking a high dose of Opana makes it much more likely that a person could fail a drug test.
Similarly, how often Opana is taken affects how long the oxymorphone remains in the system. Infrequent users of Opana are less likely to accumulate oxymorphone in their renal system and fat stores, so the drug is broken down and eliminated quicker. Taking Opana infrequently is also less likely to lead to physical and psychological dependence and tolerance, so people who consume Opana infrequently are less compelled to take more of the drug. Additionally, infrequent, lower doses mean that the oxymorphone in a patient’s system is more likely to be excreted sooner than frequent, higher doses. Someone who uses Opana very frequently may have to reach a third daily dose before the first dose has been broken down (going through the metabolism process).
More frequent administration of Opana usually leads to an increased tolerance and psychological need for the drug, resulting in higher and multiple doses consumed. Also, the more frequently a patient takes Opana, the better the chance is that the person is going to ingest a higher daily dose than someone who takes Opana in a single dose or who takes Opana infrequently; therefore, the more frequently a person takes Opana, the less efficient and the slower the elimination process is.
Passing a Drug Test
If you have a pass a drug test and are worried that Opana will show up (even after it has been discontinued), it should take about three days from the time of the last dose for the oxymorphone to be fully removed from the system, regardless of whether the Opana was in its immediate-release or extended-release format. Most of the Opana metabolites (the substances formed via the process of metabolism) should be eliminated through the urine up to five days after the last dose.
In rare cases, and if you were consuming Opana in high doses, oxymorphone may remain in the plasma for a longer period of time and be detectable on drug tests given more than three days after the final consumption.