Collapsing has a range of causes. Usually it’s because a person has fainted, and they recover quickly, but it can be due to something more serious.
Call triple zero (000) for an ambulance if someone:
- collapses while sitting or lying down
- has a seizure
- has chest pain or palpitations
- develops a sudden, severe headache
- has problems breathing
What is a collapse?
You collapse when you fall down for no obvious reason (such as when you trip or fall). A collapse may happen when you become unconscious for a few seconds, such as when you faint. You might fall to the ground and not respond to sounds or being shaken. Your pulse may become faint and you might even stop breathing.
A person collapses when their brain isn’t getting enough oxygen. When you’re on the ground, it’s easier for the heart to pump oxygen to the brain.
You should always seek medical attention if you collapse – the sooner, the better. It could be a sign something is seriously wrong, and collapsing is a common cause of injuries, especially in older people.
What causes a collapse?
Fainting occurs when your heart rate drops and the blood vessels widen. This causes blood to pool in the legs, meaning less blood reaches your brain. Fainting is also called syncope. It can be caused by triggers that include heat, standing for a long time, seeing blood, or a shock. It can also happen when you stand up quickly, especially if you are tired, dehydrated or have low blood pressure or low blood sugar.
Very occasionally, people collapse without losing consciousness – their muscles just give way. This can happen due to problems with generalised weakness and frailty, a problem with the heart or brain, a seizure or an issue affecting the inner ear.
Other, more serious, casues of collapse include:
- a heart attack
- a stroke
- a seizure
- a major illness
- an injury or accident, especially if there has been a blow to the chest or head
- a drug overdose
- alcohol poisoning
If someone collapses, follow these steps. You can remember them by thinking “Doctor’s ABCD” (for DRS ABCD).
- D – Dangers? Make sure the area is safe.
- R – Responsive? Check for a response: ask name, squeeze shoulders. If there is no response, call triple zero (000) and ask for an ambulance. If there is, make them comfortable and monitor the response.
- S – Send for help by calling triple zero (000).
- A – Open airway. Open the mouth and check the airway for foreign material. If there is foreign material, place in the recovery position and clear the airway. If there is no foreign material, leave in position. Open the airway by tilting the head back with a chin lift.
- B - Normal Breathing? Check for breathing: look, listen, feel for 10 seconds. Not normal breathing? Ensure an ambulance has been called; start CPR. Normal breathing? Place in the recovery position and monitor breathing.
- C - Start CPR. 30 chest compressions: 2 breaths. Continue CPR until help arrives or the patient starts breathing.
- D - Attach defibrillator (AED) and follow the voice prompts.
After a collapse, you should seek medical attention as soon as possible. Your doctor or the hospital will run tests including blood sugar levels, blood tests, heart tests, a urine test to rule out an infection and x-rays, especially if you injured yourself when you collapsed. You may need to have intravenous fluids, medicines or oxygen.
Do not drive after you have collapsed. Make sure there is someone with you. Follow your doctor’s instructions on eating and drinking, and take any medicines they may have given you.
How to prevent a collapse
If you are likely to faint, avoid triggers like standing up too quickly or getting dehydrated. When you change position or stand up after lying or sitting, do so slowly and carefully.
Last reviewed: June 2018