Loratab come in 3 different dosage strengths. With regular prescription dosage, the compound usually stays in your system for 48-72 hours. If you are on a very high dose, it could take up to 168 hours to completely leave your system.
It really depends on your metabolism and weight. It also depends on how long you have been taking the drug, if you have been taking over a few days it will take longer to leave your body, even longer if you have been taking it for weeks, not to forget your well being, if you have ill this will effect your bodies ability to get rid of the medication.
However if you do require to flush it out as quick as possible, the best way to do it is by drinking lots and lots of water.