Antacids Flashcards
What is acid indigestion?
A condition which results when excess acid is produced
How does acid indigestion cause acid reflux/heartburn?
If the excess acid is forced into the oesophagus
How can stomach ulcers be caused?
High acid concentrations can damage the stomach lining causing ulcers
List 4 possible causes of acid indigestion
- Over-eating
- Eating certain food
- Smoking
- Anxiety
How can histamine H2 receptor blockers help with acid indigestion?
- Histamine encourages acid secretion in stomach
- The blockers prevent the binding of histamine to the H2 receptor and so block its actions
How can proton pump inhibitors help with acid indigestion?
- 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
How do antacid compounds help with acid indigestion?
- Antacids are weak bases = can neutralise excess stomach acid
- They exhibit cyto-protective effects toward attacks against gastric mucosa
What are cyto-protective effects?
The process by which chemical compounds provide protection to human cells against harmful agents
List 3 examples of antacid
- Calcium carbonate = CaCO3
- Sodium bicarbonate = NaHCO3
- Magnesium hydroxide = Mg(OH)2
Why is it rare to find potassium in antacid medication?
It has a narrow therapeutic range - easily toxic
Why is it rare to find sodium in antacid medication?
Can cause/worsen hypertension
Why are fewer antacid medications being formulated with aluminium?
It has been linked with adverse health effects, especially with kidneys and brain developement
What is the reaction of antacids when they enter the stomach?
- They react with HCl - only excess, HCl is needed for digestion
- CO2 is produced - can cause bloating and further discomfort
What is the role of simethicone in many antacid formulations?
To reduce foaming from the reaction
What is a possible side effect of magnesium-containing antacid formulations?
May cause diarrhoea
What are the possible side effects of aluminium-containing antacid formulations?
- May cause constipation
- Can also interfere with the adsorption of phosphates in the formation of bones
What are the possible side effects of carbonate-containing antacid formulations?
May generate CO2 leading to bloating and flatulence
What is peptic ulcer disease?
- Development of a peptic ulcer in the stomach
- Thought to arise as a result of excessive amounts of gastric acid and pepsin
Name 2 treatments for a peptic ulcer
- Aluminium-containing drugs
- Antacids
Why are aluminium-containing drugs recommended for the treatment of peptic ulcers?
Mucosal protection agents
Why are antacids recommended for the treatment of peptic ulcers?
Contribute to ulcer healing
What are peptic ulcers?
Localised erosions of mucous membranes of stomach or duodenum
How do mucosal protection agents work?
Increase mucosal resistance or coat ulcer craters
How do alginates prevent acid reflux or heart burn?
Alginates float on the stomach contents to form a neutralising layer preventing reflux of stomach acids up into the oesophagus
