With the rise of online symptom-checkers, it can sometimes be tricky to know when an unexpected condition warrants a trip to A&E.
In response to the problem, Reddit users on the AskReddit area of the website were invited to flag symptoms which require immediate hospital treatment.
Both doctors and patients shared their advice and personal experiences on the thread.
We have sifted through the most popular comments to see whether the advice stands.
A person's speech becomes slurred and they are struggling to move
Such behaviour could be a sign of a stroke: when the blood supply is cut to part of the brain. This condition requires immediate medical attention. In order to raise awarenss of the signs of a stroke the NHS advises members of the public to remember the acronym FAST: Face-Arms-Speech-Time.
Face – the face may have dropped on one side, the person may not be able to smile or their mouth or eye may have dropped.
Arms – the person with suspected stroke may not be able to lift both arms and keep them there because of arm weakness or numbness in one arm.
Speech – their speech may be slurred or garbled, or the person may not be able to talk at all despite appearing to be awake.
Time – it is time to dial 999 immediately if you see any of these signs or symptoms.
A limb going numb for no apparent reason
Reddit user jjzee is likely describing peripheral neuropathy, a term used to describe a group of conditions which affect the the nerves outside the brain and spinal cord, or central nervous system.
According to the NHS, symptoms include numbess and tingling in the feet or hands; burning, stabbing or shooting pains; a loss of balance; and muscle weakness, particularly in the feet.
However, while the body advises that damage can be limited the sooner the condition is diagnosed, it does not tell the public to visit A&E in the same way as if someone is having a stroke.
A person who vomits after a head injury
While the NHS doesn't list "dark flecks under the eyes" after vomiting and diarrhea as a symptom of severe dehydration, it does warn that the condition is a medical emergency which requires immediate medical attention. A GP, out-of-hours service or NHS 111 should be contacted immediately, the website states.
The symptoms of severe dehydration include feeling unusually tired and confused; dizziness when standing that doesn't stop; and not passing urine for eight hours. Either a weak or rapid pulse and seizures could also signal severe dehydration.
A sudden headache
A sudden 'thunderclap' headache could be a sign of a subarachnoid haemorrhage, which the NHS classes as a medical emergency which requires immediate 999 help.
The condition can occur during phsyical exertion - including coughing, heavy lifting or having sex. As well as a sudden, agonising headache akin to being struck on the head, symptoms can include a stiff neck; nausea and vomting; blured vision and sensitivity to light. It can also cause stroke-like symptoms - such as slurred speech - as well as a loss of consciousness or convulsions.
One Reddit user who claimed to be a doctor stressed that most people do not need to visit A&E departments for seemingly minor injuries.
A recent study showed that nearly 75 per cent of people told to visit a hospital after calling an NHS helpline did not require emergency treatment.
To make the findings, researchers at Cambridge University researchers analysed 1,474 people who were told to go to accident and emergency by the NHS 111 service in Cambridgeshire, The Times newspaper reported.
A GP who reviewed the cases concluded that 400 of the patients should have been sent to hospital with 409 requiring no medical treatment at all. The remainder could have been seen by an out-of-hours GP.
NHS England said at the time: “NHS 111 is delivering a high quality service in the face of high demand. Only around 8 per cent of calls to NHS 111 result in advice to attend A&E."
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