Semi-solid formulation summary

Semisolid formulations




What are semi-solids?

 neither solid or liquid in nature
 examples:
o ointments
o creams
o gels
o foams
o lotios
o plasters
o suppositories

Administration routes:




 oral
 nasal
 occular: eye
 aural: ear
 parenteral
 topical
 rectal

, Anatomy of the skin




 stranum corneum: made of dead skin cells in a lipid matrix
o protects against entry of foreign substances
o part of the epidermis
 dermis:
o blood vessels, nerve endings, hair follicles, and sweat glands
o regulates temperature
o provides nutrients to the epidermis
 subcutaneous tissue:
o fat and connective tissue
o cushion and insulate

Penetrating the skin

 intercellular: molecules pass through spaces between dead cells, predominant route.
 transcellular: molecules pass through the dead cells, penetrate the cell membrane,
greatest resistance.
 transappendageal route: molecules pass through sweat glands and hair molecules.
very small contribution to drugs passing through the skin.

Transdermal drug delivery




 painless