Science dealing with collection, preparation, and standardization of drugs. Pharmacists, who must earn a qualifying degree, prepare and dispense prescribed medications. They formerly mixed and measured drug products from raw materials according to doctors' prescriptions, and they are still responsible for formulating, storing, and providing correct dosages of medicines, now usually produced by pharmaceutical companies as premeasured tablets or capsules. They also advise patients on the use of both prescription and over-the-counter drugs. Laws regulating the pharmaceutical industry are based on the national pharmacopoeia, which outlines the purity and dosages of numerous medicinal products.