Going for a drug test? Or simply trying to getting rid of the toxic effects of Opiates? Either way, the question that arises in one’s mind is ‘how long does it take for opiates to get out of your system?’ To get an answer to this question, one needs to know the pharmacokinetics of Opiates that includes, the onset of action, duration of action, metabolism, and elimination.
The time that is taken for removal of opioids also depends on the type of Opiates being used, as accurate models have a different half-life and eradication period, so in this article, the particular period will be mentioned for various types of Opiates.
What are Opiates?
Opiates or opioids are derived from the poppy plant and have been used for centuries for the treatment of pain as well as recreational purposes. They come in the class of narcotic. The psychoactive compounds present in opium plant are morphine, thebaine, and codeine.
All opiates are considered drugs with high abuse potential, and they are listed in ‘substance-control schedules’ by the DEA in almost all countries throughout the world. Opiates can come from the raw form of opium, or they can be manufactured having a structure similar to that of the natural way. The drugs included in the list are codeine, fentanyl, morphine, heroine, etc.
Classification of Opioids
The three classes of Opioids include; Natural Opiates, Synthetic Opiates, and Semi-synthetic Opiates.
Natural Opiates are derived from the naturally occurring opium and include morphine. They come from the poppy plant and the milk that is originated from the seedpods. They are considered to be less dangerous than the synthetic ones, yet they do cause some serious addiction and cause respiratory depression. This form of Opiates was consumed in the early days of its discovery for the purpose of giving anesthesia, as a remedy for nervous disorders, chronic pain, migraine, and cancer. Morphine comes in this class.
The second class is the Synthetic Opiates that contain synthetic derivatives of morphine. These include oxycodone, hydrocodone, and oxymorphone. They act on the same brain areas as the essential drugs and cause same effects. This group is human-made, and it is used to provide treatment therapy for opiate addiction. The materials employed in the production of synthetic opiates are not derived from the plant. Thus it varies from chemist to chemist.
The third class is called the semi-synthetic Opiates, and they are so called because they are derived from the class I was naturally occurring opiates. This class includes heroin, the most commonly abused opiate. It also includes alfentanil, fentanyl, levorphanol, methadone, meperidine, codeine, and propoxyphene. They were developed as a safer alternative, but they have almost the same side effects.
Mechanism of Action of Opiates
Opiates elicit their effects by acting on the opiate receptors that are present in the brain as well as the rest of the body. Opiates activate the opiate receptors and produce results that correlate with the area of the brain involved. The most, important effects produced are pleasure/ or reward and pain relief.
Opiates are responsible for the excessive release of dopamine and stimulation of the reward system located in the brain. That results in addiction. It also acts directly on the respiratory center present in the brainstem and decreases its activity resulting in slow breathing rate.
The opiate receptors are of three types; mu, delta, and kappa. Opiates bind to these receptors to alter the functioning of body and brain. The mu receptors are most important as they are involved in analgesia and respiratory depression.
Mu-type 1 receptors cause pain killing action while Mu-type 2 cause bradycardia, respiratory depression, and addiction.
Opiates also cause hyperpolarization of neurons thus inhibiting neuronal activity. That is achieved by increasing potassium ion conductance and decreasing calcium ion conductance.
Opioids show effects on medulla, spinal cord, periaqueductal area and trigeminal nucleus.
Pharmacokinetics of Opiates
Under this heading, we will be dealing with absorption of opiates, onset of action, distribution, duration of action, metabolism and elimination of Opiates
Absorption of Opiates
To check the bioavailability of Opiates i.e. the portion of drug that reaches systemic circulation, one needs to know the mode of intake of opiates. It can be given intravenously or absorbed by the cutaneous, respiratory or gastrointestinal system. I/V opiates have 100% bioavailability while those absorbed by digestive system go through first pass metabolism in the liver.
The opiates are distributed to the central nervous system mainly, and this is achieved when opiates cross the blood-brain barrier as they are lipophilic usually.
Onset of Action
The quicker you reach the commencement of the measure, the more rapid opiates cross the blood-brain barrier. That means opiates need to be highly lipophilic. Thus onset of action varies with the type of opiate being used.
For a dose of 3gm morphine, it is 15 minutes. Peak plasma levels are reached in;
- 10 minutes when injected
- 10 to 14 minutes when taken by nasal insufflations
- 30 to 45 minutes when given into muscle
- 90 minutes when consumed orally
- 2 to 4 hours when absorbed through skin
Duration of action
That depends on the type of opiate being used. The half-life of 3-gram dose of morphine is 1.5 to 4.5 hours, although the depression of respiratory system may even occur after 24 hours. Euphoric effects of morphine last from 4 to 6 hours
Metabolism of Opiates
Metabolism of opiates involves the Cytochrome p450 enzyme system, particularly CYP 2D6 and 3A4 and proteins like UDP-glucuronyltransferase.
Elimination time of Opiates and Detection on Drug Tests
Under this heading, we are going to discuss various types of opiates individually.
- Morphine: The removal of morphine starts within 2 hours of administration. 90% of morphine is excreted via urine and 10% via feces. 54% morphine binds to muscle tissue, and 36% binds to proteins while 12% doesn’t bind and remains unchanged. It is excreted in unchanged form. Morphine can be detected by drug tests up to 2 days after consumption.
- Heroin: It is detectable in urine for 24 to 72 hours and in saliva for 24 to 36 hours.
- Oxycodone: It is detectable in urine for up to three days after dosing. It can be detected in saliva for 24 to 48 hours. Elimination half-life is 3.2 hours for immediate-release oxycodone.
- Hydrocodone. It can be detected in urine even after three days of consumption. In saliva, it can be detected for up to 2 days. That means that it stays in the system for at least three days.
- Oxycontin: It has an elimination half-life of 4.5 hours. So it takes 5.5 x elimination half-life for oxycontin to be cleared from the system, i.e. 25 hours.
The half-life of opiates ranges from 1 to 9 hours. It can be detected in blood tests for up to 8 hours, in urine for up to 48 to 72 hours and hair test from 10 to 90 days. In saliva test, it is detectable from 5-10 minutes to 36 hours.
In a research study, 52 volunteers were recruited, and they were regularly tested to find the elimination time for various kinds of opiates and its metabolites. In the initial seven days of research, blood samples were taken from each volunteer, and the urine sample was taken for initial three weeks. Urine analysis was done by Fluorescence-Polarization immunoassay (FPIA) as well as gas chromatography/mass spectrometry (GC/MS). Serum was tested utilizing GC/MS.
The elimination time that was determined using GC/MS for
- Morphine was 270.3 hours, total morphine and free morphine in serum for up to 121.3 hours.
- Monoacetyl morphine in urine for up to 34.5 hours
- 11-nor-8 carboxy-delta-9-tetrahydrocannabinol in urine for up to 433.4 hours
- Codeine in urine for up to 123 hours
- Codeine in serum: 29 hours
- Dihydrocodeine in urine: 314.8 hours
The study identifies the elimination period for Opiates and its metabolites.
Factors that affect the processing of Opiates
Opiates have short half-lives as they leave the system quickly but their effects last for several hours. Factors on which the elimination of Opiates from the system depends are listed below;
- Metabolism rate of the individual
- Fat content of body
- Body mass and weight
- The state of liver and kidney, whether they are healthy or not
- How frequently is opiate used
- Quality of the opiate used
- Amount of water intake
How to explain opiates from the system quickly?
You need to reduce the elimination half-life of opiates to do so. Here are some tips;
- Increase your water intake: This is useful for light users. If you take a test, diluted urine won’t show the drug.
- Urinate as much as possible. To increase the frequency of urination, take a copious amount of water along with tea, coffee, and cranberry juice.
- Exercise regularly to boost the functioning of the body, promoting metabolism of opiates and ultimately elimination of opiates. That will also reduce body fat, thus decreasing Opiate stores in the body.