Lindsay Lohan is to be randomly tested for drink and drugs until next August.

The troubled actress - who has been sentenced to 90 days in prison and a further three months in an inpatient rehab facility for violating her probation for a driving under the influence (DUI) arrest in 2007 - will now have to stay clean and sober for over 12 months on the orders of Judge Marsha Revel.

However, she will be allowed to take five prescription medications while on probation - Nexium for heartburn, antidepressants Zoloft and Trazodone, Adderall for Attention Deficit Disorder (ADD) and painkiller Dilaudid for “dental pain”.

According to her probation report, which was released by the Los Angeles court system on Wednesday (07.07.10), Lindsay “has been on the same prescription medication for as long as she can remember. She has provided medical proof for her prescription drugs”.

The report also states the ‘Mean Girls’ star had twice tested positive for amphetamines and opiates in previous drug tests, but those were the result of Adderall and Dilaudid.

Her father Michael Lohan has long insisted his daughter is addicted to prescription drugs and in April he attempted to stage an intervention to save Lindsay from her substance abuse, and in May he wrote a letter to a judge asking for her to be ordered to rehab in relation to her DUI charge.

Lindsay, 24, must serve her time in the Los Angeles County Jail, which means she should be heading to the Century Regional Detention Facility in Lynwood, California, the only jail for women in the area.

However, it is unlikely Lindsay - who spent just 84 minutes in jail in 2007 - will serve her full-term.

Following her sentencing - which will begin on July 20 - Lindsay took to her twitter account and appeared to take aim at the international justice system.

She wrote: “It is clearly stated in Article 5 of the U.N. Universal Declaration of Human Rights that. ‘No one shall be subjected to torture or to cruel, inhuman or degrading treatment.’ (sic)”

However, it was unclear whether she was talking about her own fate or that of someone else.