Which statement about levigating agents in ointment preparation is correct?

• A. False
• B. Not applicable
• C. True
• D. Ineffective

Answer: (C)

Levigating agents are liquids used in the levigation step to wet insoluble powders and break them down into a fine, smooth paste that can be evenly incorporated into an ointment base. They work by reducing particle size and improving wetting and dispersion, making the drug distribute uniformly throughout the vehicle. The agent should be compatible with the chosen base—often miscible with the vehicle—to form a homogeneous paste, and it should not react with the active ingredient. In practice, oil-based bases commonly use a compatible oil as the levigating agent (for example, mineral oil with petrolatum), while aqueous or water-washable bases use liquids that mix well with water (like glycerin or propylene glycol). Because levigation effectively facilitates dispersion and uniformity in the final preparation, the statement about levigating agents is true.