A generic drug is identically equivalent to the brand name drug in form, safety, strength, quality and intended use. Although identical, generic drugs are substantially cheaper than their brand name counterparts.
A formulary drug is a drug that is listed on a preferred drug list from your insurance carrier. They are drugs that insurance carriers believe to be well suited to treat specific conditions, while keeping costs more manageable for both the carrier and the insured individual.
A specialty drug is a high-cost medication used to treat a chronic or complex health condition. These drugs require special handling, administration or monitoring and generally need prior authorization to order them.