Pharmaceutical formulations--suspensions and solutions.

Solutions and suspensions of drugs are used widely in the pharmaceutical industry for production of dosage forms for different routes of administration; for example, oral, parenteral and inhalation. Pharmaceutical solutions and suspensions might appear to be simple formulations but they can present many technical problems both for the manufacturing industry and for the individual pharmacist. Substances can be chemically unstable, insoluble in water, distasteful etc. Suspensions are often used as a dosage form when the drug is insoluble in water and when use of solubilizing agents is not possible. Based on method of preparation, suspensions can be divided into two categories, flocculated and deflocculated systems.