Emergency warning signs: when to call 911

The fastest signs to recognize

If you remember nothing else, call 911 for any of these:

• Chest pain, pressure or tightness lasting more than a few minutes, or that comes and goes
• Sudden weakness or numbness of the face, arm or leg, especially on one side
• Sudden confusion, trouble speaking, or trouble understanding speech
• Trouble breathing, or lips or face turning blue or gray
• Fainting or being unable to wake someone
• A seizure lasting more than 5 minutes, or a first-ever seizure
• Swelling of the lips, tongue or throat after a food, sting or medicine
• Bleeding that will not stop after 10 minutes of firm pressure
• The worst headache of your life, coming on suddenly
• Thoughts of suicide with a plan or intent, or someone who has taken an overdose

Emergency responders can start treatment on the way to the hospital, and they can alert the ER before you arrive. For a heart attack or stroke, that head start saves heart and brain tissue. Do not drive yourself if you have any of these symptoms.

Heart attack

A heart attack happens when blood flow to part of the heart muscle is blocked. Treatment works best in the first hour, so call 911 rather than waiting to see if it goes away.

Classic signs

• Chest pain or discomfort in the center or left of the chest: pressure, squeezing, fullness or aching that lasts more than a few minutes or goes away and comes back
• Pain or discomfort spreading to one or both arms, the back, the neck, the jaw or the upper stomach
• Shortness of breath, with or without chest pain
• A cold sweat, nausea or vomiting, or lightheadedness

Atypical signs: women, older adults and people with diabetes

Women, adults over 65 and people with diabetes are more likely to have a heart attack without crushing chest pain. Take these seriously, especially if they are new, sudden or come on with exertion:

• Unusual, heavy fatigue or weakness, sometimes for days beforehand
• Shortness of breath alone
• Discomfort in the upper back, shoulders, jaw or upper belly that feels like indigestion
• Nausea, vomiting, or a cold sweat with no clear cause
• Sudden dizziness or fainting

Nerve damage from diabetes can blunt chest pain, so a "silent" heart attack may show up only as breathlessness, sweating or tiredness.

What to do

1. Call 911. Do not drive yourself.
2. Chew one regular adult aspirin (325 mg) or four low-dose aspirin (81 mg each), unless you are allergic to aspirin, take a blood thinner, or have been told by a doctor not to. The 911 dispatcher can advise you.
3. Sit down and rest. Loosen tight clothing.
4. If the person collapses and is not breathing normally, start CPR (see below) and send someone for an AED (automated external defibrillator).

Related: angina, aortic dissection (sudden tearing pain into the back), pulmonary embolism and cardiac arrest.

Stroke: BE FAST

A stroke is a brain attack: a blocked or burst blood vessel in the brain. Clot-busting treatment can only be given in the first few hours, so note the time symptoms started or the last time the person was seen well.

Other stroke warning signs include a sudden severe headache with no known cause, and sudden confusion.

Symptoms that go away within minutes may be a transient ischemic attack (TIA), or "mini-stroke". A TIA is still an emergency, because it often comes before a full stroke. Call 911 even if the symptoms have faded.

Do not give a person with possible stroke aspirin, food or drink. Some strokes are caused by bleeding, and swallowing may be affected.

Breathing emergencies

Call 911 for:

• Severe difficulty breathing: unable to speak in full sentences, gasping, or using the neck and rib muscles to breathe
• Lips, tongue or fingertips turning blue or gray
• Wheezing or an asthma attack that does not ease with a rescue inhaler, or needs it again within minutes
• Choking: the person cannot cough, speak, cry or breathe (give back blows and abdominal thrusts if trained)
• Coughing up blood more than a few streaks, or sudden breathlessness with sharp chest pain (possible pulmonary embolism)
• Breathing that is very slow or shallow after taking opioids or sedatives
• In someone with COPD, new confusion, drowsiness or blue lips

While you wait, help the person sit upright, leaning slightly forward. Help them use their own rescue inhaler or prescribed oxygen as directed.

Severe allergic reaction (anaphylaxis)

Anaphylaxis is a whole-body allergic reaction that can close the airway and drop blood pressure within minutes. Common triggers are foods (peanuts, tree nuts, shellfish, fish, milk, eggs), insect stings, medicines and latex.

Signs, usually within minutes to 2 hours of exposure:

• Swelling of the lips, tongue or throat; a hoarse voice or trouble swallowing
• Wheezing, tight throat or trouble breathing
• Widespread hives, flushing or itching together with any other symptom here
• Dizziness, fainting, a fast weak pulse, or a sense that something terrible is happening
• Vomiting, cramping or diarrhea after a known allergen

What to do:

1. Use an epinephrine auto-injector right away if one is available, into the outer thigh (through clothing is fine).
2. Call 911, even if symptoms improve. A second wave of symptoms can follow hours later.
3. Lie the person flat with legs raised. If they are struggling to breathe, let them sit up. Do not have them stand or walk.
4. Give a second dose after 5 to 15 minutes if symptoms are not improving and a second injector is available.

Antihistamine pills do not stop anaphylaxis. They are not a substitute for epinephrine.

Sepsis and serious infection

Sepsis is the body's extreme response to an infection, and it can lead to organ failure and septic shock. It often starts from a common infection such as pneumonia, a urinary tract infection or an infected wound.

Call 911 or go to the ER if someone with an infection has any of these:

• Confusion, slurred speech or being very hard to wake
• Very fast breathing or breathlessness
• A fast heart rate, or very low blood pressure
• Skin that is mottled, pale, bluish, or cold and clammy
• Shivering with severe muscle pain, or a very high or very low temperature (above 38.3 °C (101 °F) or below 36 °C (96.8 °F))
• Passing little or no urine all day
• A feeling of "I might die"

Also call 911 for fever with a stiff neck, sensitivity to light, or a rash that does not fade when you press a glass against it. These can be signs of meningitis.

Severe bleeding and serious injuries

For heavy bleeding:

1. Call 911.
2. Press firmly on the wound with a clean cloth or gauze, using both hands if needed. Keep pressing for at least 10 minutes without lifting to check.
3. If blood soaks through, add more cloth on top. Do not remove the first layer.
4. For life-threatening bleeding from an arm or leg that pressure does not control, apply a tourniquet 2 to 3 inches above the wound if you have one and know how. Note the time it was applied.

Also call 911 for:

• Vomiting blood or material that looks like coffee grounds
• Black, tarry stools (melena) or large amounts of blood in the stool, especially with dizziness
• A deep wound with bone showing, or a limb that is badly deformed (possible fracture)
• Serious burns: larger than the palm of the person's hand, on the face, hands, feet, genitals or over joints, or burns that look white, leathery or charred
• Electrical injuries, even if the person seems fine (see electrical injury)
• Falls from height, car crashes at speed, or any injury where the neck or spine might be hurt. Do not move the person unless they are in danger.

Head injury

Most bumps to the head are minor, but call 911 after a head injury if the person:

• Lost consciousness, even briefly, or cannot be woken
• Has a seizure
• Vomits more than once
• Has a headache that gets worse, or slurred speech, confusion or unusual behavior
• Has weakness or numbness in an arm or leg, or trouble walking
• Has one pupil larger than the other
• Has clear fluid or blood coming from the nose or ears
• Takes a blood thinner, or is over 65, and has hit their head hard

Milder injuries with headache, dizziness or feeling foggy should be checked the same day. See concussion.

Poisoning and overdose

Call 911 if the person is unconscious, having a seizure, struggling to breathe, or cannot be woken. Otherwise call Poison Control at 1-800-222-1222 (US, free, confidential, 24 hours). Experts there can tell you whether home care is safe or you need the ER.

• Have the container or bottle with you, and know the person's age and weight and the time of exposure.
• Do not make the person vomit unless Poison Control tells you to.
• For a chemical on the skin or in the eye, rinse with running water for 15 to 20 minutes.
• For a suspected opioid overdose (pinpoint pupils, very slow or stopped breathing, blue lips, no response), give naloxone if you have it, then call 911.
• For suspected carbon monoxide poisoning (headache, dizziness and nausea in several people or pets in the same building), get everyone into fresh air and call 911.
• For alcohol poisoning, call 911 if the person cannot be woken, has slow or irregular breathing, has a seizure or is vomiting while drowsy. Lay them on their side.

Acetaminophen (paracetamol) overdose can cause no symptoms at first and still damage the liver. Call Poison Control or go to the ER even if the person feels fine. See drug overdose.

Mental health crisis

Call or text 988 (the US Suicide and Crisis Lifeline) to reach a trained counselor 24 hours a day. You can also chat at 988lifeline.org.

Call 911 if someone:

• Has made a suicide attempt or taken an overdose
• Has a plan and the means to end their life, and intends to act
• Is a danger to others, or is so confused, agitated or out of touch with reality that they cannot keep themselves safe (see psychosis)

While you wait, stay with the person. Remove guns, medicines, ropes and sharp objects if it is safe for you to do so. Listen without judging, and ask directly whether they are thinking of suicide. Asking does not put the idea in their head. See suicidal ideation and depression.

Pregnancy emergencies

Call 911 or go to labor and delivery right away for:

• Heavy vaginal bleeding (soaking a pad an hour), or bleeding with pain at any stage
• Severe abdominal pain or one-sided pain with dizziness or fainting in early pregnancy (possible ectopic pregnancy)
• A severe headache, vision changes, sudden swelling of the face or hands, or pain under the right ribs (possible preeclampsia)
• A seizure
• Fluid gushing from the vagina before 37 weeks
• The baby moving much less than usual, or not at all
• Constant, hard belly pain with a tight, rigid womb (possible placental abruption)
• Chest pain, trouble breathing, or a swollen, painful calf

The weeks after birth carry risks too. Call 911 for heavy bleeding (see postpartum hemorrhage), chest pain, trouble breathing, a seizure, or thoughts of harming yourself or your baby (see postpartum psychosis).

Children and infants

Children can become very sick quickly and may not be able to tell you what is wrong. Call 911 if a child:

• Is struggling to breathe: grunting, flaring nostrils, skin sucking in between or under the ribs, or pauses in breathing
• Has blue or gray lips, tongue or skin
• Is floppy, unresponsive, or very hard to wake
• Has a seizure for the first time, or one lasting more than 5 minutes
• Has a rash that does not fade when pressed with a glass, especially with fever
• Has swallowed a battery, magnet, medicine or chemical (also call Poison Control)
• Has signs of severe dehydration: no wet diaper or urine in 8 hours or more, no tears, sunken eyes or soft spot, very sleepy

Get same-day emergency care for:

• Any fever in a baby under 3 months of 38 °C (100.4 °F) or higher. Go to the ER. See fever in infants.
• A child of any age with fever who is unusually drowsy, will not drink, or has a stiff neck. See fever in children.
• Severe croup with a harsh, high-pitched noise on breathing in while resting
• Green (bile-stained) vomiting in a baby, or vomiting with a swollen, painful belly (possible intussusception or bowel obstruction)
• A baby with bronchiolitis who is feeding less than half the usual amount

Never give aspirin to children or teenagers. It is linked to Reye syndrome.

Other emergencies by body system

What to do while you wait for help

• Stay on the line with the 911 dispatcher and follow their instructions. They can coach you through CPR.
• Open the front door (or have someone wait outside) and turn on outside lights. Put pets away.
• Gather medicines or a list of them, and any medical ID or allergy information.
• Note the time symptoms started. This guides stroke and heart attack treatment.
• Do not give food or drink, unless told to (for example, sugar for a conscious person with low blood sugar).
• If the person is unconscious but breathing, roll them onto their side (the recovery position) so they do not choke if they vomit.

CPR for adults

If someone collapses and is not breathing, or is only gasping:

1. Call 911 and put the phone on speaker. Send someone for an AED.
2. Push hard and fast in the center of the chest: at least 2 inches (5 cm) deep, 100 to 120 times a minute. Let the chest rise fully between pushes.
3. If you are not trained, do hands-only CPR. Do not stop until help arrives or the person starts breathing.
4. Turn on the AED as soon as it arrives and follow its spoken prompts.

Infants and children need gentler compressions with two fingers or one hand. Take a CPR class through the American Heart Association or the Red Cross to learn the skills properly.

ER, urgent care or your primary care doctor?

If you are unsure, err on the side of caution. Urgent care staff will send you to the ER if needed, but that delay matters for a heart attack or stroke. Call 911 for those.

Be ready before an emergency

• Keep a written list of your medicines, allergies and conditions in your wallet or phone (most phones have a Medical ID feature readable from the lock screen).
• Save 911, 988 and Poison Control (1-800-222-1222) in your phone.
• If anyone at home has a severe allergy, keep two epinephrine auto-injectors where they can be reached, and check the expiry dates.
• If anyone at home uses opioids, keep naloxone nearby.
• Learn CPR and where the nearest AED is at work or school.

For non-urgent questions about a symptom, see the symptoms A to Z or how to research a symptom.