Dr. I had a urine  test  at pain clinic and  it came back  negative for  opiates  and I  took meds but skipped  one dose the day before  test also take  wellbutrin.  Type of  test is  the cups that show  positive or negative.  Dr didn’t  dismiss  me and said  the cups were a new type and may be unreliable  have  another  test next time  wondering  why it was negative  .. thank you