Carbomer polymer (polyacrylic acid polymer) (Carbopol (commercial name; generic abbreviation is not standardized))

Carbomer polymers, commercially referred to as Carbopol, are synthetic high-molecular-weight polyacrylic acid polymers used extensively as viscosity-enhancing agents in artificial tears and ophthalmic gels. Their highly anionic, hydrophilic structure allows them to form viscous hydrogels that adhere to the ocular surface mucin layers, creating a physical barrier that retains moisture and protects the corneal epithelium from drying and irritation. Unlike molecular targets such as receptors or enzymes, carbomer matrixes act through physical means, not by interacting with biological pathways, making them highly effective for symptomatic relief in dry eye disease and for prolonging drug retention in combination products. Safety concerns include temporary visual blurring and possible irritation, but they are generally well tolerated and widely used in ophthalmic preparations[1][2][3][4][5][7].

Other names

CarbopolPolyacrylic acid polymerCarbomer 934 (and other grades: carbomer 940 etc.)Poly(acrylic acid)

Physical barrier protection (formation of viscous gel maintains moisture, reduces evaporation, and lubricates) Enhanced precorneal residence time due to mucoadhesion and viscosity Facilitates slow drug release in drug-containing formulations