Calcium polycarbophil

Class Bulk-forming laxative
Chemistry

The calcium salt of polyacrylic acid crosslinked with divinyl glycol

Routes of administration

Oral

Absorption

Some of the calcium may be absorbed, but the rest of the substance is non-absorbable

Solubility

pKa of the polymers is 6.0; insoluble in water

Distribution

Not absorbed; remains in the bowel

Metabolism

Does not undergo any metabolism

Elimination

Eliminated largely unchanged in the stool

Time course of action

Duration of effect depends largely on the gut motility

Target receptor

Does not bind any cell receptors

Mechanism of action

Non-soluble, but absorbs up to 100 times its weight in water, exchanging calcium ions for hydrogen ions

Clinical effects

An increase in the frequency, volume, and water content of stools; potentially also hypercalcemia. Theoretically, could cause bowel obstruction in large doses

Literature reference

Danhof et al, 1982

CICM details of understanding Not specifically listed in the CICM syllabus
Mentioned around Deranged Physiology
Related SAQs