The BZD Gold Rapid Screen Test Cassette consists of a chromatographic absorbent device in which the drug or drug metabolites in the sample compete with a drug conjugate immobilized on a porous membrane for limited antibody sites. As the test sample flows through the absorbent device, the free drug in the specimen competes with immobilized antigen conjugate in the test zone by binding to the antibody-dye conjugate forming an antibody-antigen complex and preventing the formation of a rose-pink color band when the drug is at or above the detection level of 300ng/ml. In the case where free drug in the sample is below the detection level of 300ng/ml, antibody-dye conjugate is free to bind to the immobilized antigen in the test zone, producing a rose-pink color band. Furthermore, unbound dye conjugate binds to the reagent in the control zone, producing a rose-pink color band in said zone, demonstrating that the reagents and device are functioning correctly. A negative specimen produces two distinct color bands in both the test zone and the control zone. A positive specimen produces only one color band in the control zone.