Respiratory Depression (Hypoventilation)

What to do if someone may have respiratory depression

1. Try to wake them: shout their name and rub firmly on the breastbone.
2. Call 911 or your local emergency number.
3. Give naloxone (nasal spray or injection) if opioids might be involved. It is safe even if they have not taken opioids.
4. Support breathing: if they are not breathing normally, give rescue breaths or start CPR as instructed by the dispatcher.
5. If they are breathing, roll them onto their side (recovery position) so they do not choke.
6. Stay with them. Naloxone wears off in 30 to 90 minutes, and some opioids last longer, so breathing can slow again. A second dose may be needed after 2 to 3 minutes if there is no response.

How breathing is controlled

The brainstem automatically sets breathing rate and depth based on carbon dioxide and oxygen levels in the blood. Opioids, sedatives and alcohol blunt this response, so the brain does not react to rising carbon dioxide. Breathing becomes slower and shallower, oxygen falls (hypoxia) and carbon dioxide rises (hypercapnia), which further depresses consciousness. Without help, breathing stops.

Causes

Medicines and drugs

• opioids (see opioid overdose): prescription pain medicines (oxycodone, morphine, hydrocodone), methadone, and illicit drugs such as heroin and fentanyl. Fentanyl contamination of other street drugs is now a leading cause of overdose deaths
• benzodiazepines (diazepam, alprazolam, lorazepam), which can cause benzodiazepine overdose
• alcohol, including alcohol poisoning
• other sedatives: sleeping pills, barbiturates, gabapentin and pregabalin, some antihistamines and muscle relaxants
• anesthesia and procedural sedation

Combining these drugs greatly increases the risk. The FDA has a boxed warning about using opioids with benzodiazepines.

Medical conditions

• severe COPD with carbon dioxide retention
• obesity hypoventilation syndrome
• severe sleep apnea
• neuromuscular diseases: myasthenia gravis, ALS, Guillain-Barre syndrome, muscular dystrophy
• brainstem stroke, head injury or raised pressure in the skull
• severe hypothyroidism
• spinal cord injury and severe chest wall deformities

Risk factors for drug-induced respiratory depression

• starting a new opioid or increasing the dose
• high doses, especially of long-acting opioids
• mixing opioids with other sedatives or alcohol
• older age
• sleep apnea, lung disease, kidney or liver disease
• reduced tolerance after a period of not using, such as after release from prison or detox
• using alone

Signs and symptoms

• extreme sleepiness, difficulty staying awake, or unresponsiveness
• slow breathing (often under 8 to 10 breaths a minute in adults) or shallow breaths
• long pauses between breaths
• snoring, gurgling or choking sounds
• pinpoint pupils with opioids
• blue or gray lips and fingertips
• limp body, slow heartbeat
• confusion, slurred speech

Diagnosis and hospital treatment

In the hospital, teams monitor breathing rate, oxygen levels and carbon dioxide (by capnography or blood gases) and identify the cause with drug screens and other tests. Treatment includes:

• naloxone for opioids, sometimes as a continuous infusion for long-acting drugs
• oxygen and bag-mask ventilation
• breathing support: noninvasive ventilation (BiPAP) or a breathing tube and ventilator
• flumazenil for benzodiazepines is rarely used because it can cause seizures
• treatment of the underlying condition, and of respiratory failure if it develops

Prevention

• take opioids and sedatives exactly as prescribed, and never with alcohol
• avoid combining opioids with benzodiazepines or sleep medicines unless your doctor has decided it is necessary
• keep naloxone at home if you or someone you live with takes opioids. It is available without a prescription in the US
• never use drugs alone, and use fentanyl test strips where legal
• treat sleep apnea and tell surgeons and anesthetists about it
• store medicines securely away from children and others

Frequently asked questions

What are the signs of respiratory depression?

Signs include extreme drowsiness or being impossible to wake, slow or shallow breathing, long pauses between breaths, snoring or gurgling sounds, blue lips or fingertips, and pinpoint pupils if opioids are involved. It is a medical emergency.

What causes respiratory depression?

The most common cause is opioid use, especially when combined with benzodiazepines, alcohol or other sedatives. Other causes include anesthesia, severe lung disease, obesity hypoventilation, neuromuscular diseases and brain injuries.

How does naloxone work?

Naloxone blocks opioids from acting on the brain, quickly reversing opioid-induced breathing problems, often within 2 to 3 minutes. It does not reverse alcohol or benzodiazepines. Because it can wear off before the opioid does, the person still needs emergency care.

Can you die from respiratory depression?

Yes. Without help, slowed breathing can lead to brain damage from lack of oxygen, cardiac arrest and death within minutes. Calling 911, giving naloxone and supporting breathing save lives.