Pastes are semisolid products primarily intended for which use?

• A. Oral dosage forms
• B. Intravenous administration
• C. External application to the skin
• D. Inhalation therapy

Answer: (C)

Pastes are thick, solids-rich semisolid dosage forms designed to stay on the surface of the skin. The high content of solid particles and the stiff, cohesive base give pastes strong adhesion and form an occlusive barrier once applied. This makes them ideal for external application to the skin, where they can provide local therapeutic effects, protect irritated areas, or absorb moisture without easily flowing away. They aren’t suitable for internal routes like oral dosing or intravenous administration, nor are they meant for inhalation, because their viscosity and composition prevent appropriate dispersion, absorption, or administration via those routes.