GI transport + GI Problems and Pharmacological solutions - Achalasia

Question 1

What is Achalasia?

What does it cause?

Answer 1

Achalasia is a rare disease of the muscle of the lower oesophageal body and the lower oesophageal sphincter

The result is impaired relaxation of the sphincter and an absence of contractions, or peristalsis, of the
oesophagus.

Question 2

What causes achalasia?

Answer 2

Cause: largely unknown; however, there is degeneration of the oesophageal muscles and, more importantly, the nerves of myenteric plexus (the motor supply of GI tract) that control the muscles.

Question 3

What are the common symptoms of achalasia?

Answer 3

Common symptoms of achalasia include

Dysphagia

Chest Pain

Regurgitation of food and
liquids.

Question 4

What are the complications of achalasia?

Answer 4

Complications of achalasia include recurrent lung infections, oesophageal cancer and weight loss

Question 5

How can we manage achalasia?

Answer 5

1. Endoscopic balloon/ Pneumatic dilation of LOS
   (+PPI)
2. Heller’s cardio myotomy
3. Fundoplication
4. Peroral endoscopic myotomy
5. Botox (botulinum toxin type A) (muscle relaxant
6. Calcium channel blockers/nitrates

Question 6

Describe drugs for the treatment of this

Answer 6

Metoclopramide

1. Dopamine is an important neurotransmitter in the gut and promotes the
   relaxation of the LOS and stomach and inhibits gastroduodenal
   coordination. Dopamine also increases ACh release.
2. Metoclopramide BLOCKS D2 receptors 🡪 increased gastric motility and
   emptying. Also increases ACh release 🡪 increases LOS and gastric tone 🡪
   increased intragastric pressure and improved coordination and emptying.
3. Metoclopramide also excites 5-HT4 🡪 the results of this contributes to the
   above mentioned actions.
4. Indications: GORD, nausea due to surgery or cancer (chemo).

Antispasmodic agents

E.g. propantheline, mebeverine

1. Muscarinic receptor antagonist thus inhibits PSNS activity 🡪 bowel relaxes
   and reduces bowel spasm
2. Indications: IBS and diverticular disease (which may cause abdo pain)