It's been almost a week since Demi Lovato was hospitalised following a drug overdose, but the young pop singer is still being treated after suffering 'complications'.

TMZ report that Lovato, who has spoken openly about her addiction problems in the past, is still "very, very sick" and that she refused to tell the emergency services what drug she had taken - but it was a suspected opioid overdose.

People magazine, meanwhile, quote a source as saying "Demi wasn't doing well over the weekend. She came down with a fever and showed signs of infection. She is currently being treated for issues that are very common after a drug overdose."

They added: "She will need to stay in hospital for a few more days, but is expected to make a full recovery."

Meanwhile, one of the star's friends and backup dancers, Dani Vitale - whom some fans blamed for the OD - wrote an open letter to fans urging fans to continue to send love and support, rather than 'negativity towards the ones who care about Demi at this time'.