Hi my dear, The combination drug containing acetaminophen/ butal/cafn is a very good choice to control bad headaches as yours. However, I usually advise my patients to check for the efficacy of the drugs. In other words, although you might take one drug to control your headache, but it does not work for you; stop using it and try another drug or combination therapy. You are saying to take a drug test for a job. I advise not to start this medication for the moment as it contains caffeine. Usually, caffeine will jeopardize the lab results giving false positive results for opioid. After you take the test, then, can start such medication. Hope it helped my dear! Dr.Bardha