Pharmacy compounding is the art and science of creating personalized medications for human or animal patients. It involves tailored treatments prescribed by clinicians and created by pharmacists to meet the specific needs and dosage form preferences of patients.

A drug may be compounded for a patient who cannot be treated with an FDA-approved medication, such as a patient who has an allergy to a certain dye and needs a medication to be made without it, or an elderly patient or a child who cannot swallow a tablet or capsule and needs a medicine in a liquid dosage form.