During a medical emergency in 2026, the most critical "do not" is to avoid panicking, as fear can lead to "freezing" or making hasty, incorrect decisions. Do not delay calling emergency services (911, 999, or 112) while trying to assess the situation yourself; every second counts in cases of stroke or cardiac arrest. Do not move a person who has suffered a fall or a high-impact injury unless they are in immediate danger (such as a fire), as this can cause permanent spinal cord damage. Do not give the person anything to eat or drink, especially if they are semi-conscious, as this poses a major choking risk and can complicate potential emergency surgery. Additionally, do not administer medication like aspirin or nitroglycerin unless instructed by an emergency dispatcher or if the person has a known, pre-existing prescription for the specific symptom. Finally, do not overcrowd the scene; give the patient and first responders space to work and maintain a clear path for the ambulance.