Antacids

Question 1

What is acid indigestion?

Answer 1

A condition which results when excess acid is produced

Question 2

How does acid indigestion cause acid reflux/heartburn?

Answer 2

If the excess acid is forced into the oesophagus

Question 3

How can stomach ulcers be caused?

Answer 3

High acid concentrations can damage the stomach lining causing ulcers

Question 4

List 4 possible causes of acid indigestion

Answer 4

1. Over-eating
2. Eating certain food
3. Smoking
4. Anxiety

Question 5

How can histamine H2 receptor blockers help with acid indigestion?

Answer 5

• Histamine encourages acid secretion in stomach
• The blockers prevent the binding of histamine to the H2 receptor and so block its actions

Question 6

How can proton pump inhibitors help with acid indigestion?

Answer 6

• PPIs reduce the production of acid by blocking the enzyme in the wall of the stomach that produces acid
• They do not neutralise the excess acid but inhibit the initial production of HCl

Question 7

How do antacid compounds help with acid indigestion?

Answer 7

• Antacids are weak bases = can neutralise excess stomach acid
• They exhibit cyto-protective effects toward attacks against gastric mucosa

Question 8

What are cyto-protective effects?

Answer 8

The process by which chemical compounds provide protection to human cells against harmful agents

Question 9

List 3 examples of antacid

Answer 9

1. Calcium carbonate = CaCO3
2. Sodium bicarbonate = NaHCO3
3. Magnesium hydroxide = Mg(OH)2

Question 10

Why is it rare to find potassium in antacid medication?

Answer 10

It has a narrow therapeutic range - easily toxic

Question 11

Why is it rare to find sodium in antacid medication?

Answer 11

Can cause/worsen hypertension

Question 12

Why are fewer antacid medications being formulated with aluminium?

Answer 12

It has been linked with adverse health effects, especially with kidneys and brain developement

Question 13

What is the reaction of antacids when they enter the stomach?

Answer 13

• They react with HCl - only excess, HCl is needed for digestion
• CO2 is produced - can cause bloating and further discomfort

Question 14

What is the role of simethicone in many antacid formulations?

Answer 14

To reduce foaming from the reaction

Question 15

What is a possible side effect of magnesium-containing antacid formulations?

Answer 15

May cause diarrhoea

Question 16

What are the possible side effects of aluminium-containing antacid formulations?

Answer 16

• May cause constipation
• Can also interfere with the adsorption of phosphates in the formation of bones

Question 17

What are the possible side effects of carbonate-containing antacid formulations?

Answer 17

May generate CO2 leading to bloating and flatulence

Question 18

What is peptic ulcer disease?

Answer 18

• Development of a peptic ulcer in the stomach
• Thought to arise as a result of excessive amounts of gastric acid and pepsin

Question 19

Name 2 treatments for a peptic ulcer

Answer 19

1. Aluminium-containing drugs
2. Antacids

Question 20

Why are aluminium-containing drugs recommended for the treatment of peptic ulcers?

Answer 20

Mucosal protection agents

Question 21

Why are antacids recommended for the treatment of peptic ulcers?

Answer 21

Contribute to ulcer healing

Question 22

What are peptic ulcers?

Answer 22

Localised erosions of mucous membranes of stomach or duodenum

Question 23

How do mucosal protection agents work?

Answer 23

Increase mucosal resistance or coat ulcer craters

Question 24

How do alginates prevent acid reflux or heart burn?

Answer 24

Alginates float on the stomach contents to form a neutralising layer preventing reflux of stomach acids up into the oesophagus