Medically Reviewed

How Do Drugs and Alcohol Affect the Respiratory System?

5 min read · 8 sections
Substance misuse can wreak havoc on the body. While organs such as the heart and liver tend to take the spotlight in this respect, substance misuse can also be detrimental to the respiratory system, leading to serious conditions and even death. Explore the various effects on the respiratory system as well as which substances tend to have the most impact.
What you will learn:
How alcohol and drugs affect the lungs.
Respiratory effects related to alcohol, opioids, cocaine, inhalants, and marijuana.
How to treat substance use disorders.

What is the Respiratory System?

The respiratory system is made up of the various organs and tissues that allow people to breathe. It’s divided into two tracts: the upper and lower. The upper tract involves the mouth, nose, nasal cavity, sinuses, and throat. The lower track includes the larynx (aka voice box), trachea, bronchial tubes, and lungs.1

A critical function of the respiratory system is breathing, as it allows for the exchange of oxygen and carbon dioxide into and out of the body, respectively. However, breathing isn’t its only purpose. Rather, the respiratory system also works in conjunction with the circulatory system (which comprises the heart and blood vessels) to provide oxygen to the rest of the body and to remove various waste products (e.g., water vapor, gasses, and airborne particles such as dust, pollen, and pollutants). What’s more, the respiratory system also aids pH regulation in the blood.2

How Substance Misuse Affects The Respiratory System

Everything from pollen and mold to pollutants can impact the respiratory system in numerous ways; therefore, drugs can also affect the respiratory system. Additionally, the method of use, including smoking, snorting, injecting, and oral consumption, can also influence respiratory system effects.

However, when it comes to substance misuse, some of the more common associated conditions include:3-9

  • Pulmonary infections, e.g., pneumonia, tuberculosis, respiratory syncytial virus (RSV), etc.
  • Bronchospasm (i.e., a sudden narrowing of the airways).
  • Asthma exacerbation.
  • Crack lung, including labored breathing, fever, cough, or hemoptysis (i.e., coughing up blood), which can lead to respiratory failure.
  • Black phlegm, (i.e., sputum).
  • Wheeze.
  • Shortness of breath.
  • Pulmonary edema, characterized by the accumulation of fluid in the lungs.
  • Hemoptysis (i.e., coughing up blood).
  • Pulmonary granulomatosis (i.e., a nodular collection of immune cells in the lungs).
  • Irregular breathing, such as apnea (i.e., interrupted breathing) and tachypnea (i.e., rapid and shallow breathing).
  • Acute respiratory distress syndrome (ARDS), a potentially life-threatening condition that hinders lung function.
  • Respiratory depression and arrest, often caused by overdose.

It’s important to note that polysubstance use (i.e, the use of more than one drug within a short period of time) can increase the risk for severe respiratory events. Mixing drugs is never safe, as doing so can generate stronger and more unpredictable effects than using individual drugs alone. In fact, according to the Centers for Disease Control and Prevention (CDC), mixing substances can lead to slow, fast, and/or troubled breathing as well as overdose, which can involve respiratory depression and arrest.10

The following content provides a broad overview of some of the more common substances related to respiratory effects.

How Does Alcohol Affect the Respiratory System?

When one thinks about health problems associated with alcohol misuse, liver cirrhosis is typically top of mind along with pancreatitis, cardiomyopathies, neuropathies, and even dementia.3 However, the respiratory system can also be impacted by alcohol misuse.

Normally, the fine hairs (i.e., cilia) on the cells that line the respiratory tract work with the mucociliary apparatus—which is basically the body’s first line of cellular defense against various pathogens that lead to infection. Together, they remove inhaled particles, toxins, and debris from the body. However, chronic alcohol consumption alters the function of this apparatus.3 Thus, those with an alcohol use disorder (AUD) have increased susceptibility to respiratory pathogens, which can lead to various infections.3,11

Compared to those without an alcohol use disorder, people with an AUD are more likely to develop the following infections:3,11

  • Pneumonia. People with AUDs are disproportionately affected by the most common causative agent for bacterial pneumonia, namely Streptococcus pneumoniae. According to the CDC, those who misuse alcohol are 10 times more likely to contract pneumonia and 4 times more likely to die from it. Plus, roughly 20% to 30% of people hospitalized for pneumococcal infections also meet the diagnostic criteria for an alcohol use disorder. Furthermore, AUDs have been linked to oxidative stress, the latter of which can lead to poorer outcomes for pulmonary infections such as pneumococcal pneumonia.
  • Tuberculosis (TB). The underlying pathogen for TB, Mycobacterium tuberculosis, is found at high rates in those who misuse alcohol. Not everyone infected with the pathogen gets ill, and tuberculosis can stay dormant for years if the immune system is healthy. But alcohol can weaken the immune system and increase susceptibility to infection.
  • Respiratory Syncytial Virus (RSV). A major cause of respiratory infections in children and a serious problem for those with an AUD, RSV is one of the most common viral pathogens that impact the lower respiratory tract.

Acute Respiratory Distress Syndrome (ARDS) is a life-threatening complication of various events including the lung infections above.3 An AUD is associated with a 2- to 4-fold increased risk of ARDS, which is characterized by severe inflammation and problems with the epithelial barrier (which protects against pathogens, pollutants, etc.) and surfactant (a substance in the lungs that helps to maintain normal lung function).3,11

If left untreated over time, lung infections and ARDS can lead to death. However, alcohol overdose can also have severe and deadly respiratory consequences within a relatively short amount of time. Symptoms ranging from emotional discomfort to disinhibition can appear when alcohol and its metabolites accumulate in the blood faster than they can be metabolized by the body. However, in the case of overdose, alcohol can cause respiratory depression, bronchia aspiration, coma, and death.12

How Do Opioids Affect the Respiratory System?

Opioids are a class of drugs often prescribed to reduce pain or misused to produce relaxation or a high. Highly addictive and often involved in overdoses and related deaths, opioids include fentanyl, heroin, and prescription medications such as oxycodone (OxyContin), morphine, and oxymorphone (Opana).13, 14 However, both prescription and illicit opioids are often misused. In fact, according to the 2021 National Survey on Drug Use and Health (NSDUH), among people aged 12 and older, 3.3% of people (i.e., 9.2 million individuals) misused opioids in the past year.15

Although short-term, therapeutic opioid use usually doesn’t lead to serious health complications, higher doses have several side effects, including respiratory depression.16 Breathing is regulated by feedback mechanisms that involve carbon dioxide. If breathing ceases or decreases, less carbon dioxide is released through exhalation. When carbon dioxide rises, chemical receptors tell the lung to increase breathing to accommodate for it. However, opioids decrease this ventilatory response.17 As such, this added carbon dioxide can lead to severe respiratory depression, coma,  permanent brain damage, and death, especially when opioids are misused.13,17

In addition to respiratory depression, opioids can affect almost any aspect of respiration. However, the toxicity and degree of impact varies by route of administration and the type of opioid.5  Respiratory conditions associated with opioid use include:4,5,13,16,18

  • Pulmonary granulomatosis. When opioids such as heroin are injected intravenously, they’re often intentionally or unintentionally mixed with substances such as caffeine, cotton fibers, potato starch, barbiturate, talc, etc. Over time, these fillers can cause pulmonary granulomatoses, which are lung disorders characterized by small groups of immune cells. Among those who inject drugs, talc is a common cause of granulomatous disease, which can lead to pulmonary fibrosis.
  • Muscle rigidity. Any muscle group can be affected by opioid-related muscle rigidity. But it’s most concerning when it involves muscles responsible for respiration, as the condition can require intubation and the use of drugs to temporarily paralyze skeletal muscles. Most often muscle rigidity is associated with synthetic opioids such as fentanyl, but morphine has also been implicated.
  • Non-cardiogenic pulmonary edema (NCPE). Characterized by fluid accumulation in the lungs, NCPE has been associated with several opioids, such as methadone and morphine.
  • Bronchospasm. Opioids are linked to histamine release from mast cells, and the mechanism for bronchospasm is thought to involve histamine release. Thus, opioid-related histamine release leads to bronchoconstriction and airway obstruction.
  • Pulmonary infections. While minimal studies exist on the link between opioids and infections, heroin has been shown to cause various lung infections including pneumonia, and it’s been associated with ARDS. Plus, the pathogen related to tuberculosis is more prevalent in injection drug users than the general public.
  • Opioid-induced respiratory depression (OIRD). Opioid use can lead to slowed breathing, which in turn can deliver insufficient oxygen to the brain, leading to short- and long-term effects, including coma, permanent brain damage, and death. In the case of opioid overdose and polysubstance use (particularly with sedatives such as sleep medications, alcohol, and illicit substances), the risk of OIRD is elevated. This is particularly dangerous because opioids are often mixed with alcohol and/or benzodiazepines, both of which are strong sedatives. Mixing substances is always risky, but polysubstance use involving opioids can have devastating lethal effects.

How Does Cocaine and Crack Affect the Respiratory System?

Cocaine is a powerfully addictive stimulant whose recreational use is illegal. Cocaine is typically snorted, rubbed into the gums, or dissolved into a liquid and injected. However, it’s also processed into a rock crystal (aka crack) that’s smoked.19 According to at least one study, crack is the illicit substance most commonly associated with respiratory problems that require hospitalization.20

While research on the respiratory impact of cocaine and crack isn’t quite as extensive as some other substances, research still supports several associations including the following:5-7,19,20

  • Black phlegm, shortness of breath. According to one study, 75% and 65% of participants experienced black phlegm and shortness of breath, respectively, during or shortly after smoking crack.
  • Crack Lung. Patients with crack lung often experience difficult or labored breathing, fever, cough, and/or coughing up blood, which may progress to respiratory failure. Typically occurring with 48 hours of smoking crack, these symptoms comprise an acute syndrome of diffuse alveolar damage and hemorrhagic alveolitis.
  • Infections such as pneumonia.
  • Loss of smell, nosebleeds, frequent runny nose, problems swallowing.
  • Pneumothorax (i.e., air between the lung and chest wall).
  • Bronchiolitis Obliterans Organizing Pneumonia (BOOP) (i.e, a type of lung disease characterized by inflammation and scarring in the small airways and air sacs of the lungs).
  • Pulmonary edema (i.e., excess fluid in the lungs).
  • Barotrauma (i.e., pressure-related tissue injury). When smoking crack and other substances, people sometimes try to enhance drug delivery by deeply inhaling and performing a valsalva maneuver, which involves keeping the mouth and nosed closed while attempting to move air out of the lungs. This results in a large increase in interalveolar pressure across the alveoli (i.e., tiny air-filled sacs in the lungs), making them more prone to rupture.
  • Overdose-related breathing difficulties. Death from a cocaine or crack overdose is certainly possible, particularly when the substances are mixed with alcohol or heroin. Among with heart, seizure, and stroke symptoms, overdose symptoms can include difficulty breathing.

How Do Inhalants Affect the Respiratory System?

Comprising various products often found in the home and workplace, inhalants are volatile, vapor-emitting or aerosolized substances (e.g., aerosol sprays, nitrites, gases, etc.) that are inhaled for their mind-altering effects.21,22  Inhaling chemicals leads to their rapid absorption into the bloodstream via the lungs, facilitating swift distribution to the brain and other organs.21

Inhalant use can cause multiple respiratory symptoms and conditions including:23,24

  • Cough, wheezing.
  • Nasal congestion, sneezing, runny nose.
  • Phlegm.
  • Shortness of breath.
  • Emphysema.
  • Goodpasture’s syndrome, an autoimmune disorder characterized by the development of autoimmune antibodies that cause inflammation and damage to the lungs and other organs.
  • Lung tissue inflammation.
  • Abnormally fast breathing.

Inhalant misuse also can lead to a host of lethal consequences involving the cardiovascular, renal, neurological, hepatic, and respiratory systems.24 The potentially deadly respiratory effects of inhalants include:21,23,24

  • Asphyxiation. With repeated inhalations, a high concentration of inhaled fumes can develop in the lungs. This can displace oxygen, leading to oxygen deprivation, difficulty breathing, and breathing cessation.
  • Suffocation. Inhalant use can involve placing a plastic bag completely over the head and inhaling from within that bag. The effects of use can then prevent people from removing the bag, resulting in suffocation.
  • Choking. Users sometimes vomit after inhalant use and choke on the vomit.
  • Sudden sniffing death syndrome. The cause of up to half of inhalant-related death, sudden sniffing death syndrome is thought to develop as a result of cardiac arrhythmia, oxygen deficiency (i.e., anoxia), respiratory failure, and vagal inhibition.

How Does Marijuana Affect the Respiratory System?

Smoking marijuana irritates the lungs and leads to many of the same breathing complications associated with tobacco smoke.25 Marijuana use is associated with the following respiratory symptoms and conditions:25-28

  • Phlegm, coughing.
  • Lung infections.
  • Bronchitis.
  • Chronic lung inflammation and epithelial injury (including hyperplasia, i.e., abnormal increase in cell quantity).

How to Treat the Effects of Drugs on the Respiratory System

While the respiratory-related effects of substance misuse can sometimes be permanent and can lead to immediate or eventual death, other conditions and symptoms can be lessened or eliminated with medical care and abstinence. However, to create long-term improvement of physical and emotional health, treating the substance use disorder alongside these health issues is paramount.

Treatment for drug and alcohol use disorders isn’t a one-size-fits-all solution. Rather, each treatment program is tailored to the unique needs of each individual. The various levels of care of care available include:

Within these levels of care, multiple types of therapies and a variety of services and amenities are available. American Addiction Centers, which offers several facilities scattered across the country, offers the full spectrum of care. Additionally, AAC treatment centers are in-network with myriad insurance providers, which typically cover part or all treatment costs, and they accept various other payment options.

To learn more about AAC treatment options, contact an admissions navigator at or complete the insurance verification form. Caring professionals are available 24/7 to answer your questions about treatment, discuss insurance and payment options, and help you or a loved one take the first steps toward recovery today.



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