A compounding pharmacy is a type of pharmacy that prepares custom medications to fit the unique needs of patients that cannot be met with mass-produced products. Compounded medications are custom-made medications that are tailored to the specific needs of an individual patient. Compounding pharmacies can make two types of compounds: sterile and non-sterile. Compounded drugs have to follow industry standards, and the United States Pharmacopeia (USP) Convention sets those. Compounding pharmacies can be handy when there are drug shortages as well. Compounded medications may be made in various forms, including dye-free, preservative-free, alcohol-free, and/or sugar-free forms of medications. Compounding pharmacies are licensed and regulated by states in the United States. Compounding preparations of a given formulation in advance batches, as opposed to preparation for a specific patient on demand, is known as "non-traditional" compounding and is akin to small-scale manufacturing. Although almost all pharmacies are able to prepare at least simple compounded medicines, some pharmacy staff undertake further training and education to be able to prepare more complex products.