Can I Die in Sleep from Anaphylaxis? Risks and Prevention

Anaphylaxis is a severe and potentially fatal allergic reaction that requires immediate medical attention. While many people associate anaphylaxis with sudden, dramatic reactions occurring in public places, anaphylaxis can also occur during sleep, leading to fatal consequences if not properly managed.

According to the UK’s National Institute for Health and Care Excellence (NICE), anaphylaxis causes approximately 20 deaths per year in the UK alone, with hospital admissions for anaphylactic reactions rising by 615% between 1992 and 2018. 

Furthermore, a study in the journal Clinical & Experimental Allergy found that nearly 30% of anaphylaxis-related deaths occur during sleep. This raises an important question: Can you die in your sleep from anaphylaxis, and how can it be prevented?

How Anaphylaxis Can Occur During Sleep

Anaphylaxis is triggered when the immune system overreacts to an allergen, leading to a life-threatening response. Common causes include:

• Food allergies (e.g., peanuts, shellfish, dairy, eggs)
• Insect stings (e.g., bee or wasp stings)
• Medication allergies (e.g., penicillin, NSAIDs)
• Latex allergies
• Exercise-induced anaphylaxis (rare but documented)

The body’s immune response to allergens can lead to airway swelling, a drop in blood pressure, and shock, which can be fatal if untreated.

Why Can Anaphylaxis Occur During Sleep?

Anaphylaxis is unpredictable and can occur at any time—even during sleep. Here’s how:

1) Delayed-Onset Anaphylaxis:

Some allergic reactions do not happen immediately after exposure to an allergen. Biphasic anaphylaxis occurs in up to 20% of cases, where symptoms return hours after the initial reaction, sometimes during sleep.

2) Undiagnosed Allergies:

A person may be unknowingly allergic to something they consume before bed. Food-induced anaphylaxis accounts for over 50% of fatal cases in the UK.

3) Severe Asthma and Anaphylaxis Overlap:

People with asthma are at a higher risk of fatal anaphylaxis, as both conditions involve airway constriction. More than 60% of fatal anaphylaxis cases involve individuals with poorly controlled asthma.

4) Inadequate Treatment Before Sleep:

If an allergic reaction starts in the evening, but antihistamines or epinephrine (EpiPen) are not administered properly, symptoms can worsen while the person is asleep, leading to fatal outcomes.

5) Sleeping Position and Airway Blockage:

During anaphylaxis, airway swelling can progress. If someone is lying flat, fluid buildup (pulmonary edema) and airway restriction can increase the risk of suffocation.

How Common is Death from Anaphylaxis in Sleep?

While anaphylaxis is a known life-threatening condition, deaths during sleep are relatively rare but documented.

• A UK study on anaphylaxis deaths found that food-induced anaphylaxis fatalities commonly occur at night or early morning.
• A 2021 analysis of fatal anaphylaxis cases in the UK found that 56% of food-induced deaths involved delayed symptoms, which may have occurred while the person was sleeping.
• Medication-induced anaphylaxis accounts for 48% of all fatal cases, with reactions occurring unpredictably, sometimes while resting or asleep.
• The fatality rate from anaphylaxis in the UK is estimated at 0.047 per 100,000 people per year, with nighttime cases making up a small but significant percentage.

These statistics suggest that while rare, anaphylaxis-related deaths during sleep are a real risk, particularly in individuals with known allergies who do not take preventive measures. Given the severity of the condition, Anaphylaxis training UK programs has become essential in workplaces, schools, and public spaces.

Warning Signs of Anaphylaxis While Sleeping

Recognizing anaphylaxis symptoms early can be life-saving. Symptoms that may appear before or during sleep include:

• Difficulty breathing or wheezing
• Swelling of the lips, tongue, or throat
• Hives or severe skin rash
• Sudden drop in blood pressure (dizziness, fainting)
• Abdominal pain, vomiting, or diarrhea (common in food-induced anaphylaxis)
• Unresponsiveness or confusion

If a person experiences labored breathing or unconsciousness in sleep, it could indicate a progressing anaphylactic reaction.

Who is Most at Risk of Nocturnal Anaphylaxis?

Certain groups are at higher risk of experiencing anaphylaxis during sleep:

• People with undiagnosed food allergies: Many adult-onset allergies go unnoticed until a severe reaction occurs.
• Individuals with asthma: Poorly controlled asthma can worsen anaphylactic reactions.
• Those with a history of biphasic anaphylaxis: Since 20% of anaphylaxis cases involve a delayed second reaction, individuals who experience mild symptoms earlier in the day should monitor for worsening symptoms overnight.
• People who take certain medications before bed: NSAIDs (like ibuprofen) and certain antibiotics can trigger anaphylaxis in allergic individuals.
• Children and young adults: Studies show that over 60% of food-induced anaphylaxis fatalities occur in people under 30, often due to delayed treatment.

Preventing Anaphylaxis Deaths During Sleep

While anaphylaxis during sleep is dangerous, it is largely preventable with proper precautions:

1) Carry and Use an Epinephrine Auto-Injector (EpiPen)

• Only 40% of people at risk of anaphylaxis carry an EpiPen regularly. It should always be accessible, even at night.
• If an allergic reaction starts, use epinephrine immediately—delaying can be fatal.

2) Monitor for Delayed Reactions

If you’ve had an allergic reaction during the day, do not sleep alone and set alarms to check symptoms.

3) Sleep in an Elevated Position

Sleeping with your head elevated can help maintain airway patency if swelling occurs.

4) Asthma Control

Since asthma exacerbates anaphylaxis, keeping inhalers nearby and managing symptoms can reduce risk.

5) Avoid Trigger Foods and Medications Before Bed

The risk of nocturnal anaphylaxis is higher if consuming high-risk foods (peanuts, shellfish, dairy, etc.) or medications close to bedtime.

6) Wear a Medical Alert Bracelet

If anaphylaxis occurs while sleeping and emergency services are needed, a medical alert bracelet can provide critical information.

7) Have a Nighttime Emergency Plan

• Inform family members or roommates about allergies.
• Keep emergency contacts and anaphylaxis response instructions visible near the bed.

Conclusion

Yes, dying in your sleep from anaphylaxis is possible, though rare. Studies show that delayed anaphylaxis, undiagnosed allergies, and inadequate emergency response significantly increase the risk. 

However, with proper precautions, such as carrying an epinephrine auto-injector, monitoring symptoms, and avoiding allergens before bed, the risk of nighttime anaphylaxis fatalities can be significantly reduced.

Education and preparedness are crucial. If you or a loved one has severe allergies, taking proactive steps can mean the difference between life and death. Speak to a healthcare provider about allergy management, always have an emergency plan, and ensure epinephrine is within reach—because seconds matter in anaphylaxis.