Hi doc iv had a urine drugs test at work and failed on opiates.just had paracetomol/ibuprfeon/loratadine

Likely true : Most urine drug tests have high sensitivity and specificity in detecting drugs being tested for. Rarely do we see a false positive (possibly your situation). Inquire about the exact type of test. If it was a quantitative/confirmatory test (e.g. Lc/ms), then it would be hard to argue. If you truly did not take opiates, its worth a fight. If you did, its a losing battle and a sign to seek help.

Drug test: Paracetamol Ibuprofen and loratidine with their metabolites wouldn't test positive for opiates. If you have not taken any opiates within 1 week, then the test must be a false positive, or you ingested foods which could have made the test positive.