A warning from Christchurch police after three men were arrested for drugging and sexual assaults linked to an inner-city bar

The trio - aged 33, 34 and 36 - appeared in the Christchurch District Court facing charges of stupefying, supplying a Class B drug, sexual violation and making an intimate recording.

Detective Senior Sergeant Scott Anderson says this case highlights the importance of people taking care of each other on a night out.

He says it's crucial people keep an eye on their drink and stay on guard.

But Anderson says it's also important to look after your mates - and if anyone feels drowsy or suddenly 'out of it', take them to a safe place and don't leave them alone.