Leukotriene Receptor Antagonists Flashcards
Give 2 examples of leukotriene receptor antagonists
- Montelukast
- Zafirlukast
What is the mechanism of action of leukotriene receptors antagonists?
Blocks the action of cysteinyl leukotrienes in the airways
What are cysteinyl leukotrienes involved in?
Eosinophil or mast cell induced bronchoconstriction
What are the routes of delivery of leukotriene receptor antagonists?
PO
What are the indications for leukotriene receptor antagonists?
- Asthma (chronic)
- Allergic rhinitis
When should caution be used in leukotriene receptor antagonists?
- Elderly patients
- Hepatic impairment (zafirlukast only)
What can interact with leukotriene receptor antagonists?
Warfarin (zafirlukast only)
What may happen if you give warfarin and zafirlukast together?
Increased anticoagulant effect
What monitoring is required with leukotriene receptor antagonists?
- PEFR measurement (to check for improvement)
- Check FBC for agranulocytosis
What are the common side effects of leukotriene receptor antagonists?
- Headache
- Abdominal pain
- Thirst
What are the less common side effects of leukotriene receptor antagonists?
- Agranulocytosis (zafirlukast only)
- Churg-Strauss syndrome
- Hypersensitivity
- Hepatic disorders
What patient counselling is required with leukotriene receptor antagonists?
- How to take drug
- Side effects
- Jaundice
- Angio-oedema
What counselling is required regarding how to take the drug with leukotriene receptor antagonists?
Can be supplied as tablets or granules. Granules may be swallowed or mixed with cold, soft food (but not fluid) and taken immediately
What counselling is required regarding side effects with leukotriene receptor antagonists?
- Inform patients about side effects of drug.
- Warn patient about signs of agranulocytosis, and tell patients to report such side effects to their GP.
- Warn the patients about signs of Churg-Strauss syndrome
What are the signs of agranulocytosis?
Increased susceptibility to infections, e.g. sore throat
