Polycarbophil

Category

Adsorbent; Bioadhesive Material; Controlled-release Agents; Emulsifying Agents; Suspending Agents; Tablet Binder; Thickening Agents

Grade

Pharmceutical Excipients

Description

Polycarbophil occurs as fluffy, white to off-white, mildly acidic polymer powder with slightly acetic odor.

UNII

W25LM17A4W

Chemical Name

Polycarbophil

CAS Number

9003-97-8

Synonyms

Noveon AA-1

Administration route

Buccal; Ophhalmic; Topical

Dosage Form

Film; Tablet; Gel; Solution; Suspension/Drops

Stability and Storage Conditions

Polycarbophil polymers are stable, hygroscopic materials. They do not undergo hydrolysis or oxidation under normal conditions. Heat aging at temperatures for up to 2 hours does not affect the efficiency of the dry polymer. However, prolonged exposure to excessive temperatures can result in discoloration, reduced stability, and in some cases plasticization of the polymer.

Applications

Conventionally, polycarbophil is used as a thickening agent at very low concentrations (less than 1%) to produce a wide range of viscosities and flow properties in topical lotions, creams, and gels, in oral suspensions, and in transdermal gel reservoirs. It is also used as an emulsifying agent in topical oil-in-water systems. Polycarbophil is an excellent bioadhesive in buccal, ophthalmic, intestinal, nasal, vaginal, and rectal applications. Buccal tablets prepared using polycarbophil have shown high bioadhesive force and prolonged residence time, and proved to be nonirritative in in vivo trials with human buccal mucosa.

Safety

Polycarbophil polymers have a long history of safe and effective use in topical gels, creams, lotions, and ointments. They have been shown to have extremely low irritancy properties and are nonsensitizing with repeated usage. The use of these polymers is supported by extensive toxicological studies. LD50 (guinea pig, oral): 2.0 g/kg LD50 (mouse, IP): 0.039 g/kg LD50 (mouse, IV): 0.070 g/kg LD50 (mouse, oral): 4.6 g/kg LD50 (rat, oral): >2.5 g/kg LD50 (rabbit, skin): >3.0 g/kg Chronic oral toxicity No significant effects in rats or dogs were observed after being fed with resin as 5% of the diet for 61/2 months.

Incompatibilities

Heat may be generated if polycarbophil comes into contact with strong basic materials such as ammonia, sodium hydroxide, potassium hydroxide, or strongly basic amines. Polycarbophil polymers are not compatible with cationic polymers, strong acids, and high levels of electrolytes, as electrolytes tend to reduce the viscosity of polycarbophil-based gels.