A TV doctor and GP has explained the 'one symptom' which leaves her 'scared'. Dr Raj Arora who often appears on This Morning explained that NHS doctors have many red flags which they will spot immediately - and often mean something serious could be happening.

However she explained that one issue which is not seen frequently really sets alarm bells ringing - and it's to do with eyesight. On Instagram she said: "This is the one symptom that scares me as a GP, but for good reason. So, let's get into it. Now, as a doctor, there are many red flags or specific symptoms that we look at and get worried about.

"And we normally have a protocol or, you know, something to follow when it comes to that. So, ask other questions around it. But this one symptom I don't see a lot of in clinic, but when I do, I really do get concerned. So, if you have experienced sudden blurred vision or vision loss, this is categorised as an emergency. It requires immediate attention."

Dr Raj explained that people shouldn't go to see their GP if they have this - they should get someone to take them to A&E. She said: "So, you should be going to an A&E, for example, especially if it's accompanied by other symptoms like eye pain, headache, weakness, illness and this is because it could be down to a serious condition like vetal detachment, stroke, a TIA, serious eye infections, acute glaucoma and even neurological conditions like multiple sclerosis or optic neuritis.

"In essence, if you've got sudden, complete or partial vision loss or blurring and it comes on suddenly, it's really important that you do not ignore this. Don't wait to see your GP. Don't wait for an appointment. Go up to A&E. Really, really important."

Sudden vision loss is a medical emergency requiring immediate, same-day attention (A&E or 999). Key NHS symptoms include painless blacking out of vision (like a curtain falling), sudden blurred/double vision, flashing lights, new dark shadows, or severe, painful red eyes.

These can indicate serious conditions like stroke, retinal detachment, or acute glaucoma.

• you have changes in your vision, such as blurred vision, double vision, or seeing flashing lights or shapes
• you have a dark shadow moving across your vision
• you have pain in 1 or both eyes
• your eye is red and painful
• your eyes feel painful or uncomfortable in bright light

You can call 111 or get help from NHS 111 online.