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Health Effects of Opioid Use

Although opioids can be helpful medicines to relieve pain, they also have some harmful side effects and serious risks. Some of these can happen shortly after taking opioids, but long-term use also has negative side effects and increased risks.

One of the biggest concerns is the increased risk of developing an opioid use disorder (OUD), or addiction, although long-term effects of opioid use can also impact various organs and systems in the body.1 In 2019, more than 10 million Americans said they had misused opioids in the previous year, with most people misusing prescription painkillers.2 That same year, 1.6 million Americans had an OUD, with 1.4 million being addicted to painkillers.2

Short-Term Side Effects of Opioid Use

Up to 8 in 10 people who take opioids have one or more negative side effects.3 Opioid side effects may begin shortly after taking them, and commonly include:1,3

  • Confusion or lack of attention to your surroundings.
  • Constipation (dry, hard stools), since opioids interfere with how the digestive system works.
  • Drowsiness, or “nodding off.”
  • Nausea and vomiting.
  • Euphoria, or feelings of extreme pleasure.
  • Slowed breathing.

Long-Term Effects of Opioid Use on the Body

Over time, opioid use can harm the brain and is associated with risks to the cardiovascular (heart), respiratory, digestive, immune, and reproductive systems, in addition to increasing the risk of injury from falls, fractures, and overdose.6 One study found that long-term opioid use may increase the risk of opioid-related death by any cause by as much as three times.6,7

Prescription opioid misuse is also a risk factor for starting heroin use, however, only a small amount of people who misuse prescription pain relievers go on to using heroin.1 Use as well as misuse also increases the risk of a life-threatening overdose. 1

Brain Health Risks

Chronic opioid use can lead to tolerance and dependence.1 Tolerance is when you need more and more of a drug to feel the same effects.1 Dependence happens when your brain and body adapt over time to the presence of the drug so that you feel withdrawal symptoms if you stop or greatly reduce your dose.1 Both tolerance and dependence can lead to addiction.5

Opioids affect the pathway responsible for motivation and reward in the brain.1 This can also help fuel addiction because it can cause normally rewarding activities to feel less enjoyable, which may increase the motivation to keep using.1,7 Chronic opioid use increases the risk of overdose.1,9 Overdose can have a negative effect on the brain, including seizures and hypoxia, which happens when not enough oxygen reaches the brain.1,8 Hypoxia can lead to brain damage, coma, and even death.1,8

Respiratory System Risks

Since opioids slow breathing, long-term side effects of opioid abuse often impact the respiratory system (airways, lungs, and blood vessels that carry oxygen through the body). This can lead to breathing issues during sleep, such as sleep apnea and shortness of breath.6 Opioid overdose can lead to respiratory arrest, which is when breathing stops. This can cause brain damage and death from a lack of oxygen to the brain.1,8 Anybody who takes opioids is at a higher risk of overdose than those who do not, and combining opioids with depressants, such as alcohol or benzodiazepines can increase the risk of fatal overdose.6 Opioids have also been linked to increased risk of pneumonia, especially in elderly patients.6,8

Cardiovascular Health Risks

The impact of chronic opioid use on the cardiovascular system (heart and blood vessels that pump blood through the body) is an area of ongoing research.10 Long-term opioid use has been linked to a high increase of heart attack risk for patients with heart disease.10 There is also evidence that at least some opioids may contribute to a person having potentially fatal irregular heart rhythms.10

Injection opioid users are at increased risk of a number of cardiovascular risks, namely endocarditis, a dangerous bacterial infection that affects the heart valves.6,8–11 Another risk of injection drug use is contamination.11 Small particles such as fibers, rubber, or glass can get into needles and be injected into the bloodstream along with the drug.10 These unwanted particles can travel through the bloodstream to the brain and lead to stroke.10

Digestive System Health Risks

Some of the most common long-term opioid use side effects involve the digestive system.6,12 These side effects can include:3,6,11,13

  • Nausea, vomiting, bloating, and abdominal cramping. These are common short-term effects of opioid use but can linger in some chronic users.
  • Constipation (dry, hard stools), which can be severe enough to cause mental distress and even depression.
  • Bowel obstructions, which can lead to possibly fatal bowel ruptures.
  • Gastrointestinal (stomach and intestines) bleeding.

Immune System Risks

Chronic opioid use can also harm the immune system, decreasing how well it can fight off infections.6 HIV, hepatitis C, and tuberculosis are especially common among people who inject opioids.4 Sharing needles and unprotected sex can further increase your risk of HIV and hepatitis B or C.1,14 People who abuse opioids are more likely to get pneumonia, as well as have a faster progression of HIV if they are infected and continue to use.14,15

Reproductive Health Risks

Long-term opioid side effects can impact the reproductive system.6,13 Men may have erectile dysfunction, low sex drive, low levels of testosterone and androgen, infertility, and depression.4,6,13,16 Women may face irregular periods, low estrogen levels (which can lead to osteoporosis), depression, sexual issues, and infertility.4,6,13,16 Opioid use during pregnancy has been linked to low birth weight, increased risk of miscarriage, withdrawal in newborns, and birth defects.1,17

Falls and Fractures

Opioid use can cause dizziness, and long-term use is associated with an increased risk of injury from falls.6 Falls can increase the risk of fractures, especially when combined with a loss of bone mass caused by hormonal changes.6,16 Falls and fall injuries are especially common in adults age 65 years or older.18

Overdose Risks

Opioid overdose can happen after a single use, but certain factors can make it more likely.19 Taking high doses or using/misusing opioids over a long time increases the risk of overdose, as does taking illegal opioids such as heroin and imitation (counterfeit) painkillers.6,19 Opioid overdose causes dangerously slow breathing that can lead to permanent brain damage, coma, or death.1 This risk is even higher if you combine opioids with benzodiazepines or other CNS depressants, such as alcohol.19

Treatment for Opioid Addiction

If you’re worried about your opioid use and want to quit, don’t lose hope. Professional medical treatment may help you avoid or reduce the risks associated with long-term opioid  use. The first treatment step is often medical detox, where doctors and clinical staff can closely watch your progress during withdrawal and keep you as safe and comfortable as possible. This may include prescription medicines to ease symptoms and reduce cravings, such as methadone and buprenorphine1,20

Continued treatment such as rehab following detox will help you to learn skills to change unhealthy patterns of thought, incorporate healthy life skills, develop relapse prevention skills, manage triggers (the people, places, and things that tempt you to start using drugs again) and stressors, and improve family and social relationships.1

As a leading provider of addiction treatment in the country, American Addiction Centers (AAC) offers medical detox to help patients manage withdrawal in the most comfortable and safe way possible, with treatment facilities throughout the country. If you’re ready to start your recovery, we’re here to help. Call our 24/7 detox hotline at to speak with a member of our team. Alternatively, if you would like to get started online, start the process by checking your insurance coverage instantly or texting our team.

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