Britney Spears has reportedly tested free of illegal drugs and alcohol.
The troubled star has been declared "clean" after allegedly undergoing blood and urine tests during her 72-hour stay at Los Angeles' Cedars-Sinai Medical Center.
A source revealed: "She tested clean. This lady is as clean as clean can be and has been for some time."
It has been claimed Britney went on a 36-hour binge of prescription and over-the-counter medication last week, during which she took 20 Clenbuterol diet pills, 18 herbal speed tablets, 18 Piriton anti-histamine tablets, 12 Vicodin painkillers, 10 sleeping pills and eight antacid reflux tablets.
The 'Gimme More' singer was taken to hospital following a three-hour stand-off with police which began at 8pm on Thursday (03.01.08) after she refused to return her sons, two-year-old Sean Preston and one-year-old Jayden James, to ex-husband Kevin Federline. When officers arrived at the residence they claimed Britney was "under the influence of an unknown substance".
The pop superstar was held under California's '5150 Hold' legislation - which allows people to be held for 72 hours for psychiatric evaluation if they are deemed "a danger to themselves or others". She was released on Saturday (05.01.08) following a psychological assessment.
A source close to the Spears family claims Britney has been suffering from a serious psychological illness for years, saying: "There is no question she has bipolar disorder. She's been having manic episodes for a long time."
Following the incident, Britney's ex-husband Kevin has been awarded sole custody of their sons. | 
