Preferred drugs are medications recommended by the Texas Drug Utilization Review Board for their efficaciousness, clinical significance, cost effectiveness, and safety. The Medicaid Formulary contains all products, including those on the preferred drug list, available to people enrolled in Medicaid. Preferred products are available without prior authorization, although they may be subject to clinical prior authorization. Drugs identified as non-preferred on the PDL require a prior authorization. Medicaid MCOs are required to follow the PDL. The preferred drug list is published every January and July, and is also available through Epocrates.