Summary of BNF CHAPTER

GASTRO-INTESTINAL NOTES – BNF Chapter 1



1.1 DYSPEPSIA and GASTRO-OESOPHAGEAL REFLUX DISEASE (GORD)

Definitions:

1. Indigestion – Lack of adequate digestion
2. Dyspepsia – Pain, Fullness, Bloating, Nausea after eating due to disordered
digestion. Uninvestigated dyspepsia is treated with a proton pump inhibitor for 4
weeks. If no response, to this initial trial, then the patient should be tested for
H.pylori infection. If H.pylori is present, it should be treated with eradication
therapy. If symptoms persist, treatment with a proton pump inhibitor or a
histamine H2 receptor antagonist can be given for 4 weeks or intermittently to
control symptoms long term.
3. GORD – Gastro-oesophageal reflux caused by acid from the stomach entering
oesophagus; associated with heartburn, acid regurgitation and sometimes
difficulty swallowing. Initial management includes the use of antacids and
alginates. Further treatment involves Histamine H2 receptor antagonists and
proton pump inhibitors.
4. Peptic Ulcer – Ulcer in the stomach = Gastric ulcer, Ulcer in the duodenum
(intestine) = Duodenal ulcer.


1.1.1 Antacids and Simeticone

1.1.1 Antacids and Simeticone

DRUG INDICATIONS SIDE EFFECTS NOTES


ANTACIDS  Dyspepsia  Magnesium  Antacids help neutralise excess
containing stomach acid in the stomach.
Aluminium antacids tend  They are best taken when
Hydroxide to be laxative symptoms occur or are expected,
Maalox and can cause usually between meals or at
belching due to bedtime.
Magnesium carbon dioxide  They should preferably not be
Carbonate liberation. taken at the same time as other
 Aluminium drugs since they may impair
Bismuth antacids not containing absorption. Antacids can damage
recommended due to
neurotoxicty and
antacids tend enteric coatings on tablets.
encephalopathy. They to be  The words ‘low Na+’ added after
cause constipation. constipating. some preparations indicates a
sodium content of less than
Calcium antacids can
cause rebound acid
1mmol per tablet or 10ml dose.
secretion and This is directed for people with
hypercalcaemia. hypertension.


Simeticone  Dyspepsia  Simeticone is added to antacids
Detinox  Colic as an antifoaming agent to relieve
flatulence.


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, 1.1.2 Alginates

1.1.2 Alginates and Compound Preparations
DRUG INDICATIONS NOTES


Alginates with antacids  Dyspepsia  Alginates work by forming a raft of foam on top of
stomach contents. This protects the oesophagus
Peptac from being irritated by the stomach’s acidic
Gaviscon Advance contents.
 Alginates combined with antacids increase the
viscosity of stomach contents and protect the
oesophageal mucosa from acid reflux.




1.2 ANTIMUSCARINICS, ANTISPASMODICS and MOTILITY STIMULANTS

1.2 Antimuscarinics, Antispasmodics and Motility Stimulants
DRUG INDICATIONS SIDE EFFECTS NOTES


ANTIMUSCARINICS  Symptomatic  Constipation  Antimuscarinics
relief of GI  Transient Bradycardia reduce intestinal
Atropine disorders  Reduced bronchial motility.
characterised by secretions  Contra-indications
Dicycloverine smooth muscle  Urinary urgency and = Myasthenia
Kolanticon spasm e.g. retention gravis, Paralytic
Irritable bowel  Dilatation of pupils ileus, Pyloric
Hyoscine Syndrome  Photophobia stenosis, Prostatic
(Also for motion  Dry mouth enlargement.
sickness)  Flushing
Buscopan  Dryness of the skin


ANTISPASMODICS  Adjunct in GI  They have no serious  Direct relaxants of
disorders side effects. smooth muscle.
Mebeverine characterised by  Peppermint oil  Peppermint oil capsules
Colofac smooth muscle occasionally causes should not be broken or
chewed because
spasm e.g. heart burn. peppermint oil can
Peppermint Oil Irritable bowel irritate
Colpermin Syndrome mouth/oesophagus.



MOTILITY  See CNS Notes  See CNS Notes  Dopamine receptor
STIMULANTS antagonists that
stimulate gastric
Metoclopramide emptying and small
intestinal transit.
Domperidone  They also enhance
Motilium the strength of
oesophageal
sphincter
contraction.




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