Antacids

Question 1

What are indications for antacids?

Answer 1

GORD
Dyspepsia
Peptic ulcers

NSAID use

Question 2

What are the common types of antacids?

Answer 2

PPI
H2 antagonist
Compound alginate
Antacid

Question 3

What is the commonly used antacid?

Answer 3

Aluminium hydroxide

Question 4

How does aluminium hydroxide work?

Answer 4

Reaction between aluminium hydroxide and hydrochloric acid forms aluminium chloride and water

Neutralises hydrochloric acid

Inhibits action of pepsin by increasing pH

Question 5

Side effect of aluminium hydroxide

Answer 5

Constipation

Question 6

What is the commonly used compound alginate?

Answer 6

Alginic acid - brand name gaviscon

Question 7

How does alginic acid work?

Answer 7

Combines with bicarbonare to inhibit reflux

Forms a ‘raft’ of gel with near neutral pH

Question 8

Side effects of alginic acid

Answer 8

Nausea
Constipation
Diarrhoea

Question 9

What is the commonly used H2 antagonist?

Answer 9

Ranitidine

Question 10

How does ranitidine work?

Answer 10

Reversible inhibition of histamine 2 receptor

Decreased gastric acid secretion - decreased H+ concentraion

Question 11

Side effects of ranitidine

Answer 11

Stomach pain
Constipation
Nausea

Question 12

What are the commonly used PPIs?

Answer 12

Omeprazole
Lansoprazole
Esomeprazole

Question 13

What is the mechanism of action of PPIs?

Answer 13

Inhibit K+/H+ pump

Inhibits release of H+ ions into stomach

Question 14

Side effects of PPIs

Answer 14

Headaches
Nausea
Vomiting/Diarrhoea
Stomach pain 
Constipation

Question 15

Contraindications for ranitidine

Answer 15

Low eGFR

Question 16

Contraindications for PPIs

Answer 16

Patients at risk of osteoporosis should have calcium checked

Increases clearance of methotrexate