7. Gastro-intestinal smooth muscle spasm

Question 1

Gastro-intestinal spasms

Answer 1

GI contractions are painful contractions of the smooth muscle

common causes: IBS, IBD, colic

Question 2

GI spasms treament

Answer 2

• Antimuscarinic
• Antispasmodic drugs

Question 3

Antimuscarinic drugs

Answer 3

Blocks muscarinic receptors found on the GI tract to cause a wide range of sympathetic effects. It inhibits parasympathic innervation.

Question 4

Antimuscarinic drugs uses

Answer 4

Also blocks smooth muscle in the lungs and bladder, so therefore have a wide variety of uses e.g in asthma, COPD, urinary incontinence, motion sickness, arrhythmias, tremors and GI spasms

Question 5

Examples of antimuscarinics

Answer 5

• Atropine
• Hyoscine
• Propanthelene
• Dicycloverine

Question 6

MHRA warning on antimuscarinics

Answer 6

Hyoscine injections - has a risk of serious side effects like tachycardia, hypotension, anaphylaxis. This is more serious in patients with cardiac disease

Question 7

Antimuscarinics side effects

Answer 7

• Urinary retention
  caution: enlarged prostate
  contraindicated: urinary retention
• Blurred vision,
• Dry mouth
• Constipation
• confusion, drowsiness
• Glaucoma (as they raise intraocular pressure)
  caution: susceptibility
  contraindicated: closed-angle glaucoma

Question 8

Antispasmodic mechanism of action

Answer 8

Relaxes smooth intestinal muscle

Question 9

Antispasmodics list

Answer 9

Antispasmodics can be divided into two main classifications: antimuscarinics and smooth muscle relaxants

antimuscarinics
* Hyoscine
* Atropine
* Propantheline

smooth muscle relaxants
* Peppermint oil - can cause heartburn and irritation so capsules must be swallowed whole

• Mebeverine
• Alverine

Question 10

Antispasmodic contra-indications

Answer 10

Paralytic ileus (where the intestinal muscles are temporarily paralysed)