Problems associated with antacid therapy:

1. The normal pH range of the stomach is 1-2, after the administration of antacid preparation it raises the pH range at 4-5 which greatly reduces pepsin’s proteolytic action. But if the ph of the stomach falls in this range, it turns to secrete additional HCl and finally acid rebound occurs.

Ø Antacid containing Al(OH)₃ - Mg(OH)₂ (30-60ml) and NaHCO₃ (4-8gm) → failed to stimulate gastric secretion.

Ø Antacid containing Al(OH)₃ - Mg(OH)₂ (30-60ml) and CaCO₃ (4-8gm) → induced gastric secretion.

2. If the antacid preparations are sufficiently water soluble then they are readily forms absorbable ions, this may turns systemic alkalosis.

3. Antacid therapy is not suitable for Na-restricted patients, where it causes hyper-natremia significantly.

4. It may produces local effect on GIT such antacid containing Ca and al-salts after being converted to soluble salts tend to be constipating. While antacid containing Mg-salts tend to produce laxative effects.

Antacids are taken by mouth to relieve –

• heartburn
• gastroesophageal reflux disease
• acid indigestion

Peptic ulcers may require H2-receptor antagonists or proton pump inhibitors. The utility of many combinations of antacids is not clear, although the combination of magnesium and aluminium salts may prevent alteration of bowel habits.