A woman has a rare condition which makes her 'faint' when she laughs, cries or is hungover - and once almost drowned in a pool due to it.

Chelsea Coombes, 27, first realised something was wrong when she was 17 years old and felt her face drop after she laughed.

It continued to happen when she giggled and got worse - causing her head to jolt and her tongue to shut.

Chelsea went to the doctor at the time and was told she likely had sleep disorder narcolepsy and cataplexy - a sudden and brief loss of muscle tone - but failed to get an official diagnosis.

But Chelsea has gradually got worse and said her episodes are triggered by her emotions - such as when she laughs, cries and when she is hungover.