GI: ANTACIDS

Question 1

ANTACIDS: INDICATIONS

Answer 1

• Gord

- Dyspepsia

Question 2

ANTACIDS: MOA

Answer 2

• Usually a compound preparation with one ALGINATE and 1/more antacids
• Buffer stomach acids
• Alginates increase viscosity of stomach contents, reduces reflux of stomach acid into oesophagus
• They form a floating raft which separates gastric contents from the GOJ to prevent mucosal damage
• Evidence to suggest they inhibit PEPSIN formation

Question 3

ANTACIDS: SIDE EFFECTS

Answer 3

• Mg salts = diarrhoea

- Al salts = constipation

Question 4

ANTACIDS: WARNINGS

Answer 4

• Well tolerated and safe in PREGNANCY
• Compound alginates should not be given in combination with THICKENED MILK PREPARATIONS
• Na/K+ preparations should be used with caution in patients with fluid overload/hyperkalaemia (eg RENAL FAILURE)

Question 5

ANTACIDS: INTERACTIONS

Answer 5

• Can reduce serum concentrations of many drugs, so doses should be taken at different times
• The above applies to: ACE INHIBITORS, some ABs (Cephalosporins, ciprofloxacin and tetracycline), bisphosphonates, digoxin, levothyroxine, and PPIs
• Increases the alkalinity of urine, antacids increase the excretion of aspirin and lithium

Question 6

ANTACIDS: EXAMPLES

Answer 6

• Gaviscon

- Peptac