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Substance Abuse and Your Immune System

Researchers have been studying how drugs and alcohol can negatively impact the immune system since the AIDS epidemic when transmission was highest among people who used intravenous drugs. Different substances affect different organs, but overall, addictive substances devastate the immune system.

People struggling with active addiction face a higher likelihood of health complications, and it’s essential to understand the potential issues so that you can anticipate any problems and find ways to support your immune system.

Read on to learn about how substance abuse negatively impacts the immune system.

Addictive Substances and Your Immune System

Drugs and alcohol can impact the immune system in multiple ways. Each substance affects the body differently and can impact some organs more than others. Below, we’ve outlined how some of the most abused substances interfere with immune system functioning.

Alcohol’s Affect on the Immune System

Alcohol depresses the central nervous system by slowing down the body’s automatic, life-preserving functions.

In addition to maintaining healthy blood sugar levels, regulating blood clotting, and performing hundreds of other vital functions, the liver is primarily responsible for breaking down and removing toxins from the body’s blood supply.

Alcohol impedes this process, taxing the liver and causing it to work at a lower capacity. Over time, and with misuse, the liver becomes overworked, which is why alcohol is linked to several liver-related diseases, including:

  • Alcohol-related fatty liver disease
  • Alcoholic hepatitis
  • Cirrhosis

The liver fulfills an essential role in the body’s immune system – a healthy liver detects, captures, and clears bacteria and viruses. When people drink alcohol excessively for prolonged periods, they risk developing such intense scarring of the liver that it fails to function correctly. If the damage progresses to cirrhosis, the liver cannot fully recover.

Liver damage is just one example of how alcohol can negatively impact the immune system – it can also impair the function of immune cells such as macrophages and neutrophils and cause damage to the respiratory tract. As such, alcohol is associated with several respiratory illnesses, such as tuberculosis and acute respiratory distress syndrome.

How Cocaine Impacts the Immune System

Research shows that cocaine can have severe adverse effects on various cells throughout the immune system, including T cells, B cells, and NK cells. These cells are responsible for fighting infections, tumors, and cancer; cocaine disrupts these cells and makes it difficult to carry out essential processes.

Cocaine changes the cells and makes them slower to act on dangerous infections or diseases. And in the fight against disease or infection, these cells need to mobilize quickly and perform their essential functions.

Like other drugs, cocaine lowers a person’s inhibitions and increases the risk of contracting or transmitting an infectious disease.

Health Risks of Marijuana

Many people view marijuana as a relatively harmless drug, but that isn’t necessarily the case. Marijuana has been associated with a wide range of negative health consequences, including immune system impairment.

The cannabis plant contains 560 different chemicals, several of which change how the immune system functions. One of these chemicals, cannabidiol (CBD), is often marketed as an anti-inflammatory that can help relieve various conditions, from joint pain to anxiety and depression.

However, studies have shown that CBD is also an immunosuppressant. In simple terms, CBD likely lowers the immune system’s ability to fight infection, which could be especially dangerous for someone with an autoimmune condition. Many people with autoimmune disorders struggle with inflammation. If someone with an already weakened immune system takes CBD to find relief, they could unknowingly put themselves at risk for infection.

But marijuana isn’t just a health risk for immunocompromised folks; smoking marijuana can impair overall pulmonary function. Frequent cannabis smoking often results in reduced lung capacity and an increased risk for respiratory infection.

Opioids and the Immune System

The medical community began to examine opioids’ effect on the immune system at the start of the AIDS crisis. They found that not only was intravenous drug use spreading this terrible virus, but opioids themselves suppress the immune system, increasing the likelihood of infection during an already raging epidemic.

This correlation may also explain the increased risk of respiratory illness in people with an opioid use disorder. Opposingly, short-term opioid use can also stimulate the immune cells and help some people fight off infections as they occur. Yet over time, this protective effect swings in the other direction, putting chronic opioid users at a higher risk of contracting an infectious disease.

Health Risks of Different Routes of Administration

Different routes of administration have various effects on the immune system. Route of administration refers to how people use a substance and includes methods such as:

  • Inhalation (smoking)
  • Intravenous (injecting)
  • Oral (taken by mouth)
  • Insufflation (snorting)

All routes of administration can cause health problems and put the immune system at risk.

Complications From Oral Substance Use

Oral use of addictive substances includes swallowing pills or eating or drinking substances. In some ways, oral routes of administration are less risky than others, as the gastrointestinal tract and liver can process substances before reaching the bloodstream.

Nevertheless, these organs bear the brunt of the substance’s toxic effects, and chronic substance use can severely impact the stomach, liver, and esophagus.

Alcohol use, for instance, can cause substantial inflammation throughout several organs in the GI tract. In addition, it can kill many healthy bacteria living in the gut, leading to worsened overall immune system function.

Risks of Nasal Substance Use

Snorting drugs, also known as insufflation, bypasses the protective elements of the GI tract. Instead, drugs land on the mucous membranes in the nose and reach the bloodstream directly. Chronic drug use can damage these membranes, increasing your risk of infection.

Mucous membranes play a vital role in the body’s immune system, but they are still vulnerable to infection. Most people catch infections through the mucosal surfaces of the body, and damaging these membranes puts you at increased risk of having a weaker immune system overall.

Inhalation Substance Use Complications

Smoking any substance, such as marijuana, tobacco, amphetamines, or crack, irritates the lungs and makes them more prone to infection. We breathe in viruses and pathogens in the air, and when the lungs are damaged, they’re less capable of fighting off these invaders and keeping you feeling well.

Intravenous Substance Use Health Risks

Over time, as people become more tolerant of other routes of administration, they may turn to intravenous (IV) substance use in search of a stronger, faster high.

According to UCLA Health, IV use carries the risk of addiction, infection, and overdose. Sharing needles and syringes can put people at risk for blood-borne diseases and viruses such as HIV, Hepatitis C, and Hepatitis B. Any one of these viruses can devastate the immune system; people with a compromised immune system are more likely to get sick more often and experience more severe side effects.

How to Support Your Immune System

Fortunately, there is one sure way of improving immune system function after substance use: getting and staying sober. Stopping substance use is the only way to minimize your risk of exposure and protect your body while it recovers and starts to regulate after prolonged substance misuse.

You can support your recovery efforts with other healthy behaviors like mindful movement, eating healthy meals, incorporating a mindfulness practice, and getting out in nature.

If you need help to break free from a substance use disorder, don’t hesitate to reach out to our contact team and learn more about our extensive treatment options. Recovery is possible, and your body can heal with time.


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