Which of the following symptoms is a reason to call 911?

Calling 911 is critical in situations where someone is experiencing chest pain, as this symptom could indicate a serious medical condition such as a heart attack. Chest pain can be accompanied by other symptoms including shortness of breath, nausea, or discomfort in the arms, jaw, or back, which further intensifies the urgency of getting immediate medical assistance. Quick medical intervention can be lifesaving, especially in cases of a heart attack where every minute counts.

Severe headache, excessive sweating, and persistent cough are symptoms that should not be ignored but may not require immediate emergency assistance like chest pain does. Severe headaches can have many causes, including tension headaches or migraines, which may not necessitate calling emergency services. Excessive sweating can be a symptom of anxiety or other non-life-threatening conditions unless accompanied by alarming signs. Similarly, a persistent cough can indicate respiratory conditions but typically can be managed without immediate emergency care.