Which are the four types of semisolid topical preparations?

Which are the four types of semisolid topical preparations?

• A. Ointments, creams, gels, pastes
• B. Ointments, pastes, creams, suspensions
• C. Creams, gels, solutions, pastes
• D. Ointments, suspensions, aerosols, gels

Answer: (A)

Semisolid topical preparations are grouped by their consistency and vehicle into four main types: ointments, creams, gels, and pastes. Ointments are greasy, cohesive, and usually petrolatum-based with little water, forming a protective occlusive layer. Creams are emulsions—either oil-in-water or water-in-oil—giving a lighter, non-greasy feel and allowing incorporation of both oil- and water-soluble components. Gels are jelly-like networks with mostly water, non-greasy and cooling, suitable for hydrophilic drugs. Pastes are thick, stiff mixtures with a high solid content dispersed in a small amount of vehicle, offering strong protective and absorptive properties. Other topical forms like suspensions, aerosols, and solutions are liquid or gaseous systems, not semisolids, so they aren’t counted among the four semisolid topical types.

Semisolid topical preparations are grouped by their consistency and vehicle into four main types: ointments, creams, gels, and pastes. Ointments are greasy, cohesive, and usually petrolatum-based with little water, forming a protective occlusive layer. Creams are emulsions—either oil-in-water or water-in-oil—giving a lighter, non-greasy feel and allowing incorporation of both oil- and water-soluble components. Gels are jelly-like networks with mostly water, non-greasy and cooling, suitable for hydrophilic drugs. Pastes are thick, stiff mixtures with a high solid content dispersed in a small amount of vehicle, offering strong protective and absorptive properties. Other topical forms like suspensions, aerosols, and solutions are liquid or gaseous systems, not semisolids, so they aren’t counted among the four semisolid topical types.