Review prescriptions to assure accuracy, to ascertain the needed ingredients, and to evaluate their suitability. Provide information and advice regarding drug interactions, side effects, dosage, and proper medication storage. Maintain records, such as pharmacy files, patient profiles, charge system files, inventories, control records for radioactive nuclei, or registries of poisons, narcotics, or controlled drugs. Plan, implement, or maintain procedures for mixing, packaging, or labeling pharmaceuticals, according to policy and legal requirements, to ensure quality, security, and proper disposal. Assess the identity, strength, or purity of medications. Collaborate with other health care professionals to plan, monitor, review, or evaluate the quality or effectiveness of drugs or drug regimens, providing advice on drug applications or characteristics. Order and purchase pharmaceutical supplies, medical supplies, or drugs, maintaining stock and storing and handling it properly. Analyze prescribing trends to monitor patient compliance and to prevent excessive usage or harmful interactions. Advise customers on the selection of medication brands, medical equipment, or healthcare supplies. Compound and dispense medications as prescribed by doctors and dentists, by calculating, weighing, measuring, and mixing ingredients, or oversee these activities.