The following is true of aluminium hydroxide gel except

Neutralization of gastric acid (Antacids) (a) Systemic:- Sodium bicarbonate, Sod. citrate (b) Nonsystemic:- Magnesium hydroxide, Mag. trisilicate, Aluminium hydroxide gel, Magaldrate, Calcium carbonate. Aluminium hydroxide gel:- It is a bland, weak and slowly reacting antacid. On keeping it slowly polymerizes to variable extents into still less reactive forms. Thus, the ANC of a preparation gradually declines on storage. The Al3+ ions relax smooth muscle. Thus, it delays gastric emptying. Alum. hydrox. frequently, causes constipation due to its smooth muscle relaxant and mucosal astringent action. Alum. hydrox. binds phosphate in the intestine and prevents its absorption--hypophosphatemia occurs on regular use. This may: (a) cause osteomalacia (b) be used therapeutically in hyperphosphatemia and phosphate stones. Ref:- kd tripathi; pg num:-649,655