Man 'necking' a beverage
Media playback is unsupported on your device
Video

Neknomination: Out of control

#BBCtrending traces the origins of #Neknomination, taking a look at how the social drinking game spiralled out of control.

The online drinking game 'Neknomination', which involves filming oneself whilst 'necking' a drink, has gone viral on Facebook.

Participants post their videos on social media and then nominate someone else to do the same.

Its popularity has come at a price, after a teenager died in the Republic of Ireland who allegedly took part in a 'Neknomination'.

Produced by Anne-Marie Tomchak and Neil Meads.

All our stories are at BBC.com/trending

Follow @BBCtrending on Twitter and tweet using #BBCtrending