Respiratory Depression: Drug and Nondrug Causes

Respiratory depression, also known as hypoventilation, refers to abnormally high levels of carbon dioxide in the blood due to shallow breathing. Hypoventilation can be a side effect of certain medications and drugs, such as opioids, benzodiazepines, and alcohol, as well as various neuromuscular disorders. If left untreated, respiratory depression can lead to fatal complications. 

This article will go over everything you need to know about respiratory depression, including symptoms, causes, treatment options, and more.

Symptoms: Respiratory Depression and Breathing Effects

The primary symptom of respiratory depression is labored, shallow, and/or slow breathing. Normally, we breathe in oxygen through our lungs and exhale carbon dioxide as a waste product after our body has gotten the oxygen it needs. Hypoventilation makes it harder to breathe in deeply, leading to excess carbon dioxide in the blood. 

In addition to shortness of breath, symptoms of respiratory depression may include:

• Fatigue
• Daytime sleepiness
• Multiple nighttime wakings
• Morning headache
• Swollen ankles
• Depression
• Cyanosis (bluish and/or discolored skin)
• Disorientation

Drug-Related Respiratory Depression Causes

Many different medications and drugs that have a sedating or “depressive” effect on the central nervous system can lead to respiratory depression. This is especially true if you misuse drugs, take multiple drugs at once, and/or take them in excessively large doses. 

Some of the drugs that can cause respiratory depression include:

• Opioid painkillers, such as OxyContin (oxycodone) and Vicodin (hydrocodone)
• Alcohol
• Benzodiazepines, such as Valium (diazepam) and Xanax (alprazolam)
• Barbiturates, such as Luminal (phenobarbital)
• Sedatives
• Narcotics, such as heroin

Nondrug Respiratory Depression Causes

Aside from drugs, other potential causes of respiratory depression include:

Does Respiratory Depression Require Hospitalization?

Mild cases of respiratory depression may cause relatively few symptoms or no symptoms at all. Sometimes, symptoms such as fatigue and shortness of breath develop gradually over time. These cases can often be treated at home or on an outpatient basis. 

However, acute respiratory depression is a medical emergency and needs to be treated right away. If your oxygen levels are low enough (and/or your carbon dioxide levels are high enough), you may lose consciousness. Organ damage is possible without adequate treatment.

Treatments to Reverse Respiratory Depression Symptoms

Respiratory depression can often be treated with oxygen therapy. It may also be treated with:

Depending on the cause of your symptoms, your healthcare provider may also recommend:

• Lifestyle changes, such as weight loss
• Pulmonary rehabilitation, which can help you develop more effective breathing techniques
• Medications, such as bronchodilators or corticosteroids, to reduce inflammation and keep your airways open
• Positional changes to help you breathe more deeply

Risks of Untreated Respiratory Depression

Untreated respiratory depression can lead to serious and even fatal health complications, such as:

• Respiratory arrest, which happens when someone stops breathing entirely
• Cardiac arrest
• Coma
• Pulmonary hypertension (high blood pressure in the arteries of the lungs), which can lead to cor pulmonale (right-sided heart failure)

Call 911 or go to the emergency room if you or someone you know is showing signs of having stopped breathing, such as:

• Seizures
• Going limp
• Loss of consciousness
• Bluish skin

Summary

Respiratory depression, or hypoventilation, refers to excess amounts of carbon dioxide in the blood caused by slow, shallow breathing. Large doses of opioids, barbiturates, sedatives, benzodiazepines, drugs, and/or alcohol can cause hypoventilation. Other potential causes include neuromuscular disorders, chest wall deformities, lung problems, brain injuries, obesity, and sleep apnea.