JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD Pharm. D III Year PHARMACEUTICAL FORMULATIONS Previous Question Paper (July/August - 2021 - R08)

A pharmaceutical dosage form is the physical form in which a drug product is presented to the patient to ensure safe, accurate, and effective administration of the active pharmaceutical ingredient (API). It serves as a vehicle for delivering the drug to the site of action or into the systemic circulation.

The concept of dosage forms relies on several fundamental principles:

• Protection: Safeguarding the drug from environmental factors like light, moisture, or oxygen (e.g., enteric-coated tablets).
• Masking: Improving patient compliance by masking unpleasant tastes or odors of the API.
• Dose Accuracy: Providing a precise, measured quantity of the drug to ensure therapeutic efficacy and safety.
• Site-Specific Delivery: Controlling the release of the drug to a specific site in the body or at a specific rate (e.g., sustained or controlled release).
• Stability: Enhancing the chemical and physical stability of the drug product during its shelf life.

Tablet granulation is the process of forming larger particles (granules) from fine powder to improve flow properties and compressibility. The primary techniques are:

• Wet Granulation: The most common method, involving the addition of a liquid binder to a powder blend to form a damp mass. This mass is then passed through a screen to form granules, which are subsequently dried and lubricated. It is ideal for drugs with poor flow or compressibility.
• Dry Granulation (Slugging or Roller Compaction): Used for moisture- or heat-sensitive drugs. The powder blend is compressed into large, flat tablets (slugs) or passed through rollers to form a dense sheet, which is then milled and screened to produce granules.
• Direct Compression: Technically not a granulation technique, but an alternative where the drug and excipients are blended and compressed directly into tablets. This requires excipients with excellent flow and compression characteristics.
• Melt Granulation: A process where a binder that melts at a low temperature is used. The drug and binder are heated until the binder melts, acting as the granulating agent without the need for solvents or extensive drying.