Gastrointestinal Flashcards
Hyoscine butylbromide
(Antimuscarinics)
Irritable bowel syndrome (for its antispasmodic effect)
(Acetylcysteine)
Paracetamol metabolised into N-acetyl-p-benzoquione imine (NAPQI). NAPQI is hepatotoxic, and detoxified with conjugation with glutathione. Acetylcysteine replenishes glutathione supple in paracetamol poisoning.
Also has antioxidant effects. Also breaks disulphide bonds in mucus to decrease viscosity.
Antidote for paracetamol poisoning
Prevent renal injuring from radiographic contrast
Reduce viscosity of respiratory secretions
(Alginates and antacids)
Antacids buffer stomach acids. Alginates increase viscosity of stomach content, preventing reflux.
Gaviscon
(Alginates and antacids)
Gatro-oesophageal reflux disease
Dyspepsia
Antacids
(Alginates and antacids)
Gatro-oesophageal reflux disease
Dyspepsia
(Aminosalicylates)
Mechanism unknown, but has anti-inflammatory and immunosuppressive effects.
✖Aspirin hypersensitivity
Mesalazine
(Aminosalicylates)
+ corticosteroids to treat ulcerative colitis
Sulfasazine
(Aminosalicylates)
Rheumatoid arthritis
(Antiemetics, dopamine D2-receptor antagonist)
Vomiting centre in medulla receives input from chemorecpetor trigger zone, solitary tract nucleus, vestibular system and higher neurological centres. D2 receptor is main receptor in chemoreceptor trigger zone. Dopamine also has pro-kinetic effect in gut, promoting gastric emptying
✖Neonates
✖Cardiac conduction abnormalities
✖Intestinal obstruction/perforation
Metoclopramide
(Antiemetics, dopamine D2-receptor antagonist)
Treatment of nausea and vomiting
Domperidone
(Antiemetics, dopamine D2-receptor antagonist)
Treatment of nausea and vomiting
(Antiemetics, histamine H1-receptor antagonists)
Histamine (H1) and acetylcholine (muscarinic receptors) predominate in vomiting centre as well as communication with vestibular system. Drugs blocking H1 receptors useful in treating nausea and vomiting especially from motion and vertigo.
Cyclizine
(Antiemetics, histamine H1-receptor antagonists)
Nausea and vomiting especially due to motion sickness or vertigo
Cinnarizine
(Antiemetics, histamine H1-receptor antagonists)
Nausea and vomiting especially due to motion sickness or verticgo
Promethazine
(Antiemetics, histamine H1-receptor antagonists)
Nausea and vomiting especially due to motion sickness or vertigo
(Antiemetics, serotonin 5-HT3-Receptor antagonists)
High number of serotonin receptors in chemorecptor trigger zone of medulla and in gut, released in response to emetogenic stimuli. Serotonin antagonists effective in nausea and vomiting caused by nausea inducing chemicals and visceral stimulation (e.g. gut infection, radiotherapy)