Troubled singer Amy Winehouse has been admitted to hospital after suffering "dangerous levels" of dehydration following her battle to kick her drugs habit.

The Back to Black hitmaker has been seeking treatment at a rehabilitation centre for a week, but was admitted to the private London Clinic on Wednesday evening under a false name.

A source tells British newspaper the Sun, "Amy was looking very pale and thin.

"She looked ropey and exhausted. Let’s hope she hasn’t taken a turn for the worse."

Winehouse’s father Mitch confirmed his daughter is suffering "horrific" withdrawal symptoms.

He says, "Amy is OK. She is making progress but will be in rehab for a long time." - Wenn