Proton Pump Inhibitors Flashcards
Example of a PPI
Omeprazole
How do PPIs work?
PPIs reduce gastric acid secretion.
They act by irreversible inhibiting H+/k+ ATPase in gastric parietal cells. This is the proton pump responsible for secreting H+ and generating gastric acid. An advantage of targeting the final stage of gastric acid production is that they are able to suppress gastric acid production almost completely
Indications of PPIs
Peptic ulcer disease and NSAID-associated ulcers: prevention and treatment
GORD and Dyspepsia: Symptomatic relief
Eradication of H.Pylori infection, in which they are used in combination with antibiotic therapy.
Contraindications of PPIs
They can disguise the symptoms of gastric cancer so it is important not just to treat symptoms without considering, and if appropriate, investigating their cause.
There is epidemiological evidence to suggest that PPIs, particularly high doses over a long period of time in the elderly can increase the risk of fracture. Patients are risk of osteoporosis should therefore be identified and treated as appropriate.
Side effects of PPIs
GI disturbances and headache
By increasing the gastric pH, PPIs may reduce the body host defense against infection; evidence of increased risk of C.Diff in patients taking PPIs.
Prolonged treatment can cause hypomagnesaemia, which if severe, can lead to tetany and ventricular arrhythmia.
Possible interactions of PPIs
There is some evidence to suggest that PPIs, especially omeprazole, reduce the anti platelet effect of clopidogrel by decreasing its activation by Cytochrome P450 enzymes. Current evidence suggests that lansoprazole and pantoprazole have a lower propensity to interact with clopidogrel and so are preferred when prescribing alongside clopidogrel.
Elimination
Renal
Patient information
Oral (taken with or without food, best taken in the morning) and injections available. Dose depends on drug and indication. Generally the lowest effective dose should be used for the shorted period possible.
Explain treatment is to reduce stomach acid and will hopefully improve symptoms and allow their ulcer to heal.
Ensure patient is aware of the duration of the therapy (7 days course to eradicate H.Pylori). Inform patient to report any red flag symptoms (weight loss, swallowing difficulty) if they arise.
Success will be judged either using endoscopy to confirm healing or resolution of symptoms.