Croscarmellose sodium

• BPCroscarmellose Sodium
• JPCroscarmellose Sodium
• Ph. Eur.Croscarmellose Sodium
• USP–NFCroscarmellose Sodium

Ac-Di-Sol; cross-linked carboxymethylcellulose sodium; Disolcel; Explocel; modified cellulose gum; Pharmacel XL; Primellose; Solutab; Vivasol; E468

Cellulose, carboxymethyl ether, sodium salt, cross-linked · [74811-65-7]

Polymer, mixture or material of variable composition — no single molecular formula applies.

Disintegrant

Typical concentrations: 0.5–5% tablets · 10–25% capsules · Dosage forms: Solid

A 'superdisintegrant' used in tablets and capsules, in both direct compression and wet granulation. Typical concentrations: tablet disintegrant 0.5–5.0% (commonly about 2%); capsule disintegrant 10–25%. In wet granulation it is often split between the granules and the external phase.

An odourless, white or greyish-white powder. It is an internally cross-linked form of carboxymethylcellulose sodium that swells strongly in water but does not dissolve.

Degree of substitution

0.60–0.85

pH

5.0–7.0 (1% w/v aqueous dispersion)

Swelling

swells rapidly to about 4–8 times its original volume in water

Settling volume

10–30 mL (USP–NF test)

Solubility

insoluble in water; practically insoluble in acetone, ethanol and toluene

Stable, although hygroscopic. Store in a well-closed container in a cool, dry place; moisture uptake before compression can reduce its effectiveness.

Incompatible with strong acids and with soluble salts of iron and some other metals such as aluminium, mercury and zinc. Its efficiency can be lowered by strongly acidic media and by cationic drugs that bind to its carboxyl groups.

Alkali cellulose, made by steeping wood pulp or cotton linters in sodium hydroxide, is reacted with sodium monochloroacetate to give carboxymethylcellulose sodium. Part of the carboxymethyl groups are then allowed to esterify with hydroxyl groups of neighbouring chains under acidic conditions and heat, producing the cross-links without an added cross-linking agent.

Not absorbed after oral administration and generally regarded as non-toxic and non-irritant. Very large oral amounts may have a laxative effect, but the quantities in tablets are far too small for this.

Observe normal precautions for the quantity handled. Avoid creating dust; eye protection, gloves and a dust mask are recommended.

Accepted as a food additive in Europe (E468). Included in the FDA Inactive Ingredient Database (oral capsules, granules, sublingual tablets and tablets) and in non-parenteral medicines licensed in Europe.

Carboxymethylcellulose calcium; carboxymethylcellulose sodium; crospovidone; sodium starch glycolate.

Croscarmellose sodium acts by rapid wicking and swelling, and its fibrous particles keep working after wet granulation, although some activity is lost. Because it is anionic, possible interaction with weakly basic, cationic drugs and its effect on dissolution should be checked.