Warning signs: call 911 or go to the ER
Do not wait for them to pass or try to handle them with a hotel visit if you or your companion has any of these signs:
- Chest pain or pressure, or pain in the arm, jaw, neck or back, with shortness of breath, weakness or feeling faint.
- Trouble breathing that starts suddenly or gets worse, or shortness of breath at rest.
- Signs of a stroke: see the BE-FAST rule below.
- Loss of consciousness, fainting, sudden confusion or difficulty waking the person.
- A seizure that lasts more than 5 minutes, is the first one, happens again soon after, occurs in water, during pregnancy or in a person with diabetes who loses consciousness, or comes with an injury or trouble breathing or waking up.
- Heavy bleeding that does not stop with direct pressure, or vomit or stools with a lot of blood.
- A severe allergic reaction: swelling of the lips, tongue or throat, trouble breathing or swallowing, or widespread hives with dizziness.
- Severe abdominal pain or pain that does not ease, especially with a hard belly.
- Fever with a stiff neck, severe headache, confusion or sensitivity to light.
- Severe dehydration: unable to drink or keep fluids down, passing little or no urine, drowsiness or confusion.
- Injury: a blow to the head followed by vomiting, drowsiness or confusion; a traffic accident; a possible broken bone or a deep wound.
How to recognize a stroke: the BE-FAST rule
If any of these signs appears suddenly, call 911 right away and note the time it started:
- B, balance: sudden loss of balance or coordination.
- E, eyes: sudden loss of or change in vision.
- F, face: ask the person to smile. Does one side of the face droop?
- A, arms: ask the person to raise both arms. Does one arm drift down?
- S, speech: ask the person to repeat a simple phrase. Is the speech slurred or strange?
- T, time: call 911 right away.
The CDC advises against driving yourself to the hospital or having someone drive you: it is better to call 911 so an ambulance is sent.
How to call 911 in Mexico City
911 is the emergency number in Mexico. In Mexico City it is run by the C5 and answers 24 hours a day, 365 days a year, including medical emergencies. When you call, calmly say:
- What is happening.
- Where you are: address, hotel name, room number and a landmark.
- What time it started.
- How many people are affected.
If you are staying at a hotel, also tell the front desk. If you do not speak Spanish, ask the staff to help you give the address.
What to bring to the ER
- Passport or official ID.
- Your travel or health insurance policy and the insurer's assistance phone number.
- A list of your medicines with the generic name and dose, plus your allergies and medical conditions.
- A credit or debit card.
- A charged phone and a family member's contact information.
The CDC suggests listing medicines by their generic name, because brand names vary from country to country.
Hospitals in Mexico City and paying for care
Mexico City has public and private hospitals with 24-hour emergency departments. This guide does not recommend any particular one.
Private hospitals usually ask for a payment guarantee before or at the time of care, such as a credit card, a deposit or your insurer's authorization. Call your insurer's assistance line as soon as possible, as many policies require, and keep your invoices and medical reports for reimbursement. If you have a warning sign, do not delay care because of this paperwork.
What a hotel doctor can and cannot treat
A general physician making a house call or hotel visit can assess and treat mild conditions, for example:
- Mild respiratory infections, such as a cold, sore throat or cough without trouble breathing.
- Gastroenteritis or diarrhea without warning signs (see the traveler's diarrhea guide).
- Minor cuts and scrapes.
- Mild symptoms from the altitude (see the altitude guide).
It does not replace a hospital. For any of the warning signs in this guide, or if imaging, oxygen, surgery or a hospital stay may be needed, call 911 or go to the ER. If a warning sign appears during the visit, the doctor will tell you to go to the ER.
Frequently asked questions
Does 911 work in Mexico City?
Yes. 911 is the emergency number in Mexico. In Mexico City it answers 24 hours a day, 365 days a year, including medical emergencies.
Do I need insurance to go to the ER?
If you have a warning sign, get care first. Private hospitals usually ask for a payment guarantee, such as a card, a deposit or your insurer's authorization, so keep your policy and assistance phone number at hand.
Can a hotel doctor replace a visit to the ER?
No. A hotel doctor can treat mild conditions, such as a mild respiratory infection, gastroenteritis without warning signs or a minor cut. For chest pain, trouble breathing, signs of a stroke or any other warning sign, call 911.
Sources
- C5 de la Ciudad de México. Emergencias 9-1-1 [Spanish]. Mexico City Government. Accessed October 19, 2026. c5.cdmx.gob.mx
- Hagmann SHF, Norton SA. What To Do When Sick Abroad. In: CDC Yellow Book 2026: Health Information for International Travel. Centers for Disease Control and Prevention; 2025. cdc.gov
- Centers for Disease Control and Prevention (CDC). Signs and Symptoms of Stroke. Accessed October 19, 2026. cdc.gov
- Centers for Disease Control and Prevention (CDC). About Heart Attack Symptoms, Risk, and Recovery. Accessed October 19, 2026. cdc.gov
- World Health Organization (WHO). Meningitis. Fact sheet. Accessed October 19, 2026. who.int
- Foreign, Commonwealth & Development Office (FCDO), UK Government. Mexico travel advice: Health. GOV.UK. Accessed October 19, 2026. gov.uk
- MedlinePlus. Recognizing medical emergencies. US National Library of Medicine. Accessed October 19, 2026. medlineplus.gov
- Centers for Disease Control and Prevention (CDC). First Aid for Seizures. Accessed October 20, 2026. cdc.gov