The opioid class is a category of synthetic and semisynthetic drugs derived from the opium poppy. For the most part, these legal and illegal drugs are derived from morphine, which is synthetized from opium. Morphine is a generic painkiller used for intense pain, usually in hospitals, but it is sometimes prescribed for use at home. Other opioid drugs that have medical uses include oxycodone and hydrocodone-based drugs, like Percocet, OxyContin, Vicodin, Norco, and Lortab. Fentanyl and Dilaudid are also powerful narcotic painkillers, most often used to treat extreme chronic and end-of-life pain. Variations of narcotic painkillers, like carfentanil, are used in veterinary practices involving large animals, like elephants, bears, or horses.
There are also illegal versions of all of these drugs available on the black market due to an epidemic of opioid addiction that is sweeping the US. One of the most common illicit narcotic opioids available is heroin, which was a brand name painkiller in the late 19th century; however, the drug was found to have no medical value, and it is now Schedule I on the Drug Enforcement Administration’s list of scheduled drugs. Legal painkillers like hydrocodone and oxycodone are Schedule II, meaning that they have important medicinal value, but they are also very habit-forming. As regulations around prescription painkillers have become tighter, more people have turned to heroin and illicit versions of painkillers found for sale illegally. Many drug dealers are cutting heroin with other narcotics like fentanyl to increase potency, which has led to a series of opioid overdoses and deaths.
How Do Opioids Trigger Addiction?
Opioid drugs bind to nerve cells, called opioid receptors, that are found in in the brain, spinal cord, and some nerve clusters in the stomach. The opioid system in the body acts naturally after an injury to dull pain, although this sensation does not last for very long. Opioid drugs, on the other hand, bind to these receptors and dull pain for varying amounts of time. When these drugs are bound to their neurons, the brain reacts by releasing more dopamine, leading to a feeling of relaxation and euphoria. Dopamine is associated with the brain’s risk/reward system, so addiction often takes hold as a person feels rewarded for ingesting these medications over time.
Even under a doctor’s supervision, a person can develop a physical dependence on, and tolerance to, opioid medications. These are powerful drugs, and if a person needs to take them to treat chronic pain, then their body will rely on the influx of opiates to feel normal. They will also stop responding to the original levels of the drug in the same way, so the person will feel the need to take more. Under a doctor’s supervision, especially if the medication is needed on a long-term basis, the physician can monitor their patient for signs of addiction or abuse and adjust dosages as necessary. If a person becomes addicted to opioid drugs, they may feel desperate cravings for more and begin to seek opioids out from other sources.
Once a person begins to struggle with addiction, they not just experience withdrawal symptoms when they attempt to stop taking the opioid; they will also experience cravings and compulsive behaviors around ingesting the drug. Opioid withdrawal is rarely dangerous, but the psychological consequences of addiction can lead a person to relapse soon after their first attempt at detox. If the person has medical supervision during the withdrawal process, the chances of relapse are greatly reduced due to the continual medical supervision provided. As a result, medical detox is recommended for opioid withdrawal.
Effects on the Brain from Opioid Abuse
Opioid drugs are designed to be potent, and many of them, including Percocet and Vicodin, are designed to act quickly to relieve pain. Other illicit versions, including heroin, are designed to act quickly to induce an intense high. The opioid receptors are also associated with some body systems, including digestion and breathing, so changes to this area of the brain affect systems in the body.
Since opioids bind to specific receptors in the brain, spinal cord, and a nerve cluster in the stomach, these powerful chemicals will have both short-term and long-term effects on the brain. These changes include the following:
- Cognitive impairment: Even when taken as a prescription, larger doses of opioid drugs can lead to drowsiness or lethargy. People who take opioids can have difficulty concentrating due to this drowsiness or for other reasons that are not well understood. Being high, or experiencing euphoria, can also lead to difficulty concentrating, so nonmedical doses of opioids can lead to additional impairment. A side effect of large doses of heroin includes a phenomenon known as “nodding,” when a person experiences periods of drowsiness and alertness after the initial rush from heroin wears off.
- Brain structure changes: Some studies have shown that opioid use can change areas of the brain, even when used for a short period of time. One study shows that morphine use for one month increased the volume of some areas of the brain and decreased others; this condition persisted over four months after the study group stopped taking morphine.
- Brain damage due to oxygen levels: Because opioids reduce the rate of breathing, even at normal prescription doses, the reduced oxygen in the bloodstream can contribute to brain damage. This process is not well understood yet, but hypoxia can cause long-term brain damage in people who use opioids for chronic pain, as well as in people who struggle with opioid abuse for a long time.
- Addiction: This is a complicated, chronic illness that is influenced by many factors, including genetics, environment, family history, and brain structure. Ultimately, addiction is a disease of the brain. It is not just a mental health issue involving psychology; it’s a condition of brain chemistry too. Exposure to intoxicating substances, including opioids, can trigger addiction.
Effects on the Body from Opioid Abuse
There are many side effects associated with opioid abuse, or long-term ingestion of opioids, which can change the body in addition to affecting the brain. Changes to major systems resulting from opioid addiction or abuse are outlined below.
- The gastrointestinal system: Early side effects of opioid use, even as prescribed, can include stomach upset and constipation. Many people who receive opioid prescriptions may also receive a prescription for a stool softener to help digestion function normally. Long-term abuse, or ingestion of large doses of opioids, can also lead to nausea, vomiting, and gastrointestinal bleeding. The last symptom was found primarily in elderly patients at a rate of about 14 incidents out of 1,000 prescriptions, which is an identical rate to NSAID painkillers like ibuprofen. Constipation is the most common gastrointestinal side effect, and it reportedly occurs in 40-95 percent of people.
- Respiratory problems: Opioids cause respiratory depression, or shallow or reduced breathing. When monitored by a physician, a person taking prescription painkillers can receive help if this condition leads to a dramatic decline; however, when a person struggles with addiction to opioids and is not monitored by medical professionals, reduced breathing can lead to a lack of oxygen reaching the brain and other body systems. It is also the primary cause of death during overdose.
- The endocrine system: A person who struggles with long-term abuse of high-dose opioids can experience changes in their endocrine system, specifically related to sex hormones. Immediate side effects include changes in sex drive, including a reduced sexual experience; however, persistent reduction in endocrine production can lead to infertility, fatigue, depression, anxiety, reduced muscle mass, osteoporosis, impotence in men, and menstrual cycle changes in women.
- Hyperalgesia: Although prescription opioids are designed to treat moderate to severe pain, long-term or high-dose abuse of these drugs can create an increased sensitivity to pain. The consistent presence of opioids in the brain can lead to an increased sensitivity to pain signals coming from other areas of the body, since the brain believes it is constantly in pain. This can lead to a triggering of the fight-or-flight response when a person attempts to detox, and it can also increase the potential for long-term disability in people with serious injuries. In fact, prescribing narcotic painkillers within six weeks of an injury statistically doubles a person’s risk of disability one year later. Other studies of workers’ compensation claims involving back injury and pain show that opioid prescriptions increased the length of claims of disability rather than reducing the length of those claims. This complex interaction of the brain and body highlights the difficulty of ending an addiction to or dependence on opioids.
Signs of Opioid Addiction
When a person develops an addiction to opioid medications, many parts of their life will change. They may look different and behave differently. It is important to understand the signs of addiction in the event that a loved one begins to change.
Emotional and Behavioral Signs
When a person struggles with addiction, including addiction to opioids, there are several behavioral changes that can indicate their condition. Some of these include:
- Feeling anxious about maintaining a supply of the drug or finding the next dose of the drug
- Compulsively taking the drug
- Inability to stop taking the drug or moderate doses even when the person wants to
- Spending a lot of time taking the drug, or finding the next dose, to the detriment of other parts of life
- Running out of prescription medications early
- Experiencing intense cravings for the drug
- Avoiding friends, family, work, school, or other responsibilities to take the drug
- Escalating use of the drug, including taking higher doses or taking the drug more frequently
- Developing a tolerance to the drug or needing to take more to feel the original effects
- Developing a dependence on the drug or needing it to feel “normal”
- Experiencing withdrawal symptoms when attempting to stop the drug
- Switching ingestion methods (e.g., snorting instead of taking orally, or injecting the drug)
- Switching drugs to get a more intense effect (e.g., escalating from OxyContin to heroin)
- “Doctor-shopping,” or going to multiple doctors to get multiple prescriptions
- Finding illicit sources for the drug when unable to obtain prescriptions
- Avoiding discussions about drug use
- Becoming irritated or aggressive when asked about drug use
- Lying about drug use
- Stealing to acquire the drug
- Difficulty remembering events
- Drowsiness, fatigue, or oversleeping
- Nausea or vomiting
- Pinpoint pupils
- Experiencing withdrawal symptoms when unable to take the drug
- Collapsed or clogged veins, “track marks,” or signs of infection on the skin due to injecting drugs
- Weakened immune system
- Increased sensitivity to pain
- Reduced breathing or shortness of breath
Withdrawal Symptoms and Supervised Detox
Entering a rehabilitation programs means going through detox, which can involve a taper or replacement therapies like buprenorphine or Suboxone. Medical detox is essentially controlled and medically monitored withdrawal. This process, when supervised by medical professionals, is not dangerous. Medications can control withdrawal symptoms to ease the body off dependence on the drug and allow the person to enter a rehabilitation program without intense cravings or physical symptoms.
Withdrawal symptoms are different for each person, and withdrawal length can vary depending on how long the person has taken opioids and how large their dose was. Withdrawal can also vary depending on which opioids a person abused. For example, if a person struggled with addiction for a short period of time to a low dose of hydrocodone, they may not feel symptoms as intensely as a person who struggled with heroin addiction for a few years. However, the experience of the intensity of withdrawal can vary greatly by individual, although general symptoms and timeline can be similar. Typically, the most intense withdrawal symptoms pass within one to two weeks.