Hypromellose Acetate Succinate

Synonyms: Aqoat; Aqoat AS-HF/HG; Aqoat AS-LF/LG; Aqoat AS-MF/MG; cellulose, 2-hydroxypropyl methyl ether, acetate succinate; HPMCAS.

Description: Hypromellose acetate succinate is a white to off-white powder or granules. It has a faint acetic acid-like odor and a barely detectable taste. Hypromellose acetate succinate is available in several grades, according to the pH at which the polymer dissolves (low, L; medium, M; and high, H) and its predominant particle size (cohesive fine powder, F; or free-flowing granules, G).

Chemical Name: Cellulose, 2-hydroxypropylmethyl ether, acetate hydrogen butanedioate

Controlled-release agent; solubility enhancing agent; enteric coating agent; film-forming agent; sustained-release agent.

• Hypromellose acetate succinate is commonly used in oral pharmaceutical formulations as a film coating, as well as an enteric coating material for tablets or granules.

• It is a solubility enhancing agent via solid dispersion.

• Hypromellose acetate succinate is insoluble in gastric fluid but will swell and dissolve rapidly in the upper intestine.

• For aqueous film-coating purposes, a dispersion of hypromellose acetate succinate fine powder and triethyl citrate (as a plasticizer) in water is commonly utilized.

• Organic solvents can also be used as vehicles for applying this polymer as a film coating.

• Hypromellose acetate succinate may be used alone or in combination with other soluble or insoluble binders in the preparation of granules with sustained drug-release properties; the release rate is pH-dependent.

• Dispersions of poorly soluble drugs with hypromellose acetate succinate are prepared using techniques such as mechanical grinding, solvent evaporation, and melt extrusion.

Hypromellose acetate succinate is incompatible with strong acids or bases, oxidizing agents, and sustained levels of elevated humidity

The safety and pharmacological profiles of hypromellose acetate succinate are similar to those of other ether and ester derivatives of cellulose. All nonclinical studies reported in the literature identify no target organs for toxicity by hypromellose acetate succinate. 

Observe normal precautions appropriate to the circumstances and quantity of material handled. Hypromellose acetate succinate dust may be irritant to the eyes. Excessive dust generation should be avoided to minimize the risks of explosions. Avoid contact with open flame, heat, or sparks. Avoid contact with acids, peroxides, and other oxidizing materials. Eye protection is recommended.

Carboxymethyl cellulose; cellulose acetate; cellulose acetate phthalate; cellulose, microcrystalline; ethylcellulose; hypromellose; hypromellose phthalate; hydroxyethyl cellulose; hydroxypropyl cellulose; methylcellulose.