Emergency Warning Signs: General Information

What It Is

A medical emergency is a sudden illness or injury that may threaten life or cause lasting harm without immediate care. Organizations such as the American College of Emergency Physicians, the American Heart Association, and MedlinePlus publish lists of commonly cited warning signs to help the public recognize when emergency help may be needed.

These lists are examples, not checklists. Emergencies can look different from person to person, and symptoms not listed here can also be serious. This page does not assess any individual situation and is not a substitute for emergency services or professional medical judgment.

In the US, 911 connects callers to emergency medical services. Emergency dispatchers are trained to ask questions and give instructions while help is on the way. Calling emergency services is generally recommended over driving oneself when symptoms such as chest pain or stroke signs are present, because paramedics can begin care right away.

Common Terminology

911

The emergency phone number in the US and Canada for police, fire, and emergency medical services.

Emergency medical services (EMS)

The system of trained responders, such as paramedics and EMTs, who provide care before and during transport to a hospital.

Poison Help line

A free, confidential US hotline (1-800-222-1222) that connects callers to their local poison control center, staffed by experts 24 hours a day.

988 Suicide & Crisis Lifeline

A free, confidential US service available by call or text at 988 for people in suicidal crisis or emotional distress, and for those worried about someone else.

BE FAST

A memory aid for stroke warning signs: Balance, Eyes, Face drooping, Arm weakness, Speech difficulty, Time to call 911.

Anaphylaxis

A severe, potentially life-threatening allergic reaction that can affect breathing and blood pressure.

Urgent care

A walk-in clinic for illnesses or injuries that need prompt attention but are not life-threatening; it is not a substitute for an emergency department.

Commonly Cited Warning Signs

Health organizations commonly list the following as examples of warning signs that may indicate a medical emergency. This is not a complete list.

• Chest pain or pressure, especially if sudden, severe, or accompanied by shortness of breath, sweating, nausea, or fainting.
• Difficulty breathing or shortness of breath that is severe or sudden.
• Signs of stroke, such as sudden face drooping, arm or leg weakness or numbness, trouble speaking, loss of balance, or sudden vision changes.
• Fainting, sudden collapse, or unresponsiveness.
• Sudden, severe headache, often described as the worst headache of one's life.
• Bleeding that will not stop, or coughing or vomiting blood.
• Sudden confusion, seizures, or difficulty staying awake.
• Swelling of the face, lips, or throat, or trouble breathing after exposure to an allergen.

Other Situations Commonly Treated as Emergencies

Beyond specific symptoms, certain situations are generally treated as emergencies by health organizations.

• Serious injuries, such as major burns, head injuries, deep wounds, or suspected broken bones from a major accident.
• Possible poisoning or overdose, especially if the person is unconscious, having trouble breathing, or having seizures.
• Thoughts of suicide with a plan or immediate danger to oneself or others.
• Sudden, severe abdominal pain, particularly if the abdomen is rigid or very tender.
• High fever with a stiff neck, confusion, or a rash that does not fade when pressed.
• Signs of severe dehydration or illness in infants, such as unusual sleepiness or not feeding.

Key US Contact Numbers

These services are free and available 24 hours a day in the United States. Numbers differ in other countries.

• 911: for possible life-threatening emergencies requiring police, fire, or emergency medical services.
• Poison Help, 1-800-222-1222: for questions about possible poisonings, medicine mix-ups, or chemical exposures; if a person is unconscious, not breathing, or having seizures, people are advised to call 911.
• 988 Suicide & Crisis Lifeline, call or text 988: for suicidal thoughts, emotional distress, or substance use crises, including for someone worried about another person.
• Many health insurance plans and clinics also offer nurse advice lines for non-emergency questions.

What to Expect When Calling 911

Knowing what usually happens can make a call feel less overwhelming. This is a general description.

• The dispatcher will usually ask for the location first, so knowing the address or nearby landmarks helps.
• Callers are typically asked what happened and about the person's breathing and responsiveness.
• Dispatchers may give instructions, such as how to perform CPR, while responders are on the way.
• Staying on the line until the dispatcher says it is okay to hang up is generally advised.
• Having a list of the person's medicines and medical conditions ready can help responders.

Emergency, Urgent, and Routine Care: General Information

Health systems describe different settings for different levels of need. These descriptions are general and are not a guide for any specific situation.

• Emergency departments are designed for serious or life-threatening conditions and are open 24 hours a day.
• Urgent care clinics generally treat problems that need prompt attention but are not life-threatening, such as minor cuts or sprains.
• Primary care offices handle ongoing health needs, check-ups, and many non-urgent concerns.
• Telehealth and nurse advice lines are often used for general questions about where to seek care.
• Health organizations generally advise that when it is unclear whether a situation is an emergency, it is safer to call 911 or seek emergency care.

Questions to Ask a Healthcare Professional

General questions people often find useful to bring to an appointment:

• What are the commonly cited warning signs of a heart attack and a stroke?
• What is the difference between an emergency department and an urgent care clinic?
• What kinds of situations is the Poison Help line designed for?
• What does the 988 Suicide & Crisis Lifeline offer, and who can contact it?
• What information is helpful to keep ready in case of an emergency?
• Are there first aid or CPR classes available in the community?
• How do warning signs of serious illness differ in infants and older adults?

Sources

This guide was written in plain language from the following authoritative references.

1. Emergency Medical Services — MedlinePlus (U.S. National Library of Medicine)
2. Poison Control — Health Resources and Services Administration (HRSA)
3. 988 Suicide & Crisis Lifeline — 988 Suicide & Crisis Lifeline

Related Guides

• SymptomsChest PainGeneral information about chest pain: what it is, common associated causes, how it is evaluated, and when it is generally treated as an emergency.
• SymptomsWhen Chest Pain Requires Medical AttentionGeneral education on chest pain warning signs that medical organizations describe as emergencies, and when chest pain is commonly evaluated.
• SymptomsShortness of BreathGeneral information about shortness of breath (dyspnea): common associated causes, how it is evaluated, and warning signs treated as emergencies.
• SymptomsAbdominal PainGeneral information about abdominal pain: common associated causes, how it is evaluated, and warning signs generally treated as emergencies.
• SymptomsHeadacheGeneral information about headaches: common types, associated causes, how they are evaluated, and warning signs treated as emergencies.
• SymptomsDizzinessGeneral information about dizziness and vertigo: common types and causes, how they are evaluated, and warning signs treated as emergencies.