GI Flashcards
Indications for PPI
- Prevention and treatment for PUD
- Treatment for GORD and dyspepsia
- Eradication of helicobacter pylori
Side effects for PPI
-Abdominal pain
- constipation
- diarrhoea
- Headache
- Hypomagnesaemia
Contraindication for PPI
- can mask symptoms of gastric/oesophageal cancer
- Osteoporosis
Monitoring for PPI
- Investigation should be carried out if symptoms persists after medication or if any alarm symptoms arise
- For GORD - review annually
- if prolonged use(>1yr) then check serum magnesium
- If withdrawing from prolonged therapy- reduced dose and frequency
Patient education for PPI
- Ensure duration is made clear
- Report alarming symptoms like : weight loss, swallowing difficulty, vomiting blood, altered
blood in the stool
Key interaction for omeprazole
clopidogrel
MOA for PPI
- Proton pump inhibitors (PPIs) reduce gastric acid secretion. They act by irreversibly inhibiting H+/K+-ATPase in gastric parietal cells.
- This is the ‘proton pump’ responsible for secreting H+ and generating gastric acid.
Examples of PPI
Omeprazole, Lansoprazole, esomeprazole
Example of H2 receptor antagonist
ranitidine, cimetidine, famotidine
Indications for H2 receptor antagonist
- PUD-2nd line after PPI
- GORD and dyspepsia -2nd line
Side effects for H2 receptor antagonist
- usually mild
- bowel disturbances
- Headache and dizziness
contraindication for H2 receptor antagonist
Dose reduced in renal impairment
Monitoring for H2 receptor antagonist
Same as PPI
- Investigation should be carried out if symptoms persists after medication or if any alarm symptoms arise
- For GORD - review annually
- if prolonged use(>1yr) then check serum magnesium
- If withdrawing from prolonged therapy- reduced dose and frequency
Patient education for H2 receptor antagonist
Ensure that the intended duration of therapy is clear and
emphasise the need to report any ‘alarm’ symptoms (e.g. weight loss,
swallowing difficulty, vomiting blood, altered blood in the stool),
should they arise
Key interaction for H2 receptor antagonist
interacts with drugs metabolised by cytochrome P450 enzymes, notably including aminophylline/theophylline, amiodarone,
citalopram, phenytoin, quinine, and warfarin.
MOA for H2 receptor antagonist
- Histamine H2-receptor antagonists (‘H2-blockers’) reduce gastric acid secretion.
- Acid is normally produced by the proton pump of the gastric parietal cell, which secretes H+ into the stomach lumen in exchange for drawing K+ into the cell.
- The proton pump is regulated by, among other
things, histamine. - Histamine is released by local paracrine cells and binds
to H2-receptors on the gastric parietal cell. - Via a second-messenger system, this activates the proton pump. Blocking H2-receptors therefore
reduces acid secretion. - However, as the proton pump can also be
stimulated by other pathways, H2-blockers cannot completely suppress gastric acid production.
Indications for alginates and antacids
GORD
Dyspepsia
Side effects for alginates and antacids
- Diarrhoea (Magnesium salts)
- Constipation (Aluminium salts)
Contraindication for alginates and antacids
Na and K containing prep-use with caution in renal failure
Monitoring for alginates and antacids
red flag symptoms then review with specialist
Patient education for alginates and antacids
- relive within 20 min
- taken after mealtimes and before bed
- Temporary measure
- Discuss lifestyle modification
Key interaction for alginates and antacids
can reduced serum conc of drugs like ACE inhibitor , some antibiotics like ciprofloxacin, digoxin, levothyroxine and PPI
MOA of alginates and antacids
- Antacids work by buffering stomach acid. Alginates act to increase the viscosity of the stomach contents, which reduces the reflux of acid into the oesophagus.
- After reacting with stomach acid they form a floating ‘raft’, which separates the gastric contents from the gastro-oesophageal junction to prevent mucosal damage.
- There is some evidence that they also inhibit
pepsin production
Examples alginates and antacids
Gaviscon
Examples of laxatives
macrogol 3350, lactulose (osmotic laxatives) senna, docusate sodium (stimulant laxatives)
Indication for laxative
- Constipation
- Bowel prep
- Hepatic encephalopathy (lactulose only)
Side effect for laxative
- Flatulence
- Abdo cramps
- diarrhoea
- nausea
- Melanosis coli (Long term use)
Contraindication for laxative
intestinal obstruction
Monitoring for laxative
- stool chart
- electrolyte
Patient education for laxative
- for it work need to drink plenty of water
- if passing more than 2 or 3 soft stool per day then dose should reduced or stopped
Key interaction for laxative
- Macrogols
- starch based thickeners
Indication for metoclopramide
Prophylaxis and treatment of nausea and vomiting
Side effects for metoclopramide
- Diarrhoea
- extrapyramidal effects
- QT-interval prolongation
- Arrythmias
Contraindication
- neonates, children and young adults
- Parkinson’s disease
Monitoring for metoclopramide
resolution of symptoms
Patient education for metoclopramide
- Only short term is recommended
- Stop and seek medical attention if side effects occur
Key interaction for metoclopramide
- antipsychotic
- dopaminergic agents
Indication for loperamide
- Symptomatic treatment of acute diarrhoea
- Chronic diarrhoea
- Faecal incontinence
- Pain of bowel colic in palliative care
Side effects for loperamide
- GI disorders
- Headache
- Nausea
Contraindication for loperamide
- ulcerative colitis
- children under 12
Key interaction for loperamide
- Clozapine
- Dronedarone
- Tepotinib
- Velpatasvir
