All hydrophilic ointment bases have limited capacity to retain added liquids because viscosity changes occur.

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

Answer: (A)

Hydrophilic ointment bases are water-miscible and rely on a thickening network, often from polymers like polyethylene glycols, to hold the liquid in place. When you add liquids, especially water, they mix with the base and dilute this network. That dilution lowers the viscosity and disrupts the gel-like structure that keeps the liquid incorporated. Because the base can’t maintain its integrity as more liquid is added, there’s a limited capacity to retain that added liquid before the mixture becomes too dilute or separates. Therefore, the statement is true: hydrophilic ointment bases have only a limited ability to hold added liquids because viscosity changes accompany dilution.