Preparation of Pastes
- S-1-Pharmaceutics I
- Feb 27
- 1 min read
Updated: Apr 9
Definition
Pastes are semi-solid topical preparations containing a high proportion of solid substances dispersed in a base.
They are thicker and stiffer than ointments, allowing them to adhere to the skin for extended periods.
Pastes are used to protect, soothe, and provide localized effects.
Preparation Methods
1) Levigation
Solid ingredients are ground into fine powder and then mixed with the paste base to ensure even distribution of the active ingredient.
2) Incorporation
Ingredients are mixed together using a mortar and pestle or similar equipment until a homogenous mixture is achieved.
The base typically consists of fatty substances like petrolatum and solid ingredients such as zinc oxide or starch.
3) Fusion
Ingredients are melted together, then cooled to form a solid paste.
This method is less common but used when components need to be melted.
Types of Pastes
Fatty pastes
Absorptive pastes
Emulsion pastes
Uses
Pastes are used for:
Protection
Absorption
Wound care
Antipruritic and anti-inflammatory effects
Antifungal and antibacterial treatments
