Britney Spears could face jail time after her DUI arrest if pills in her possession contain narcotics.MEGA Britney Spears could be facing jail time following her shocking DUI arrest . According to a Friday, March 6, report, the pop star, 44, may be placed behind bars once it's determined if the substances she was carrying with her contained narcotics. Spears was cuffed for driving under the influence, and a source revealed she was also carrying Adderall, which she retrieved during a recent trip to Mexico. The singer reportedly often travels to the tropical destination to get the drug. Britney Spears reportedly had an unknown substance in tow while driving.MEGA The pills are still being tested and it has not yet been confirmed what Spears was carrying with her. Insiders told TMZ the pills will be examined to see whether they are laced with fentanyl, cocaine, meth or other substances. Although a DUI does not typically merit jail time, the introduction of narcotics can change thi...