Resp Drugs Flashcards
What are the two classes of β2-adrenoceptors Agonists?
- SABA (short acting beta agonist)
- LABA (long acting beta agonist)
What is the first line SABA used?
Salbutamol
What are the two types of LABA used?
- Salmeterol
- Formoterol
What conditions are β2-adrenoceptors Agonists used to treat?
- Asthma
- COPD
What is the mechanism of β2-adrenoceptors Agonists?
- Coupled with G proteins
- Binding stimulates adenylyl cyclase which then converts ATP to cAMP
- Phsophodiesterase breaks down cAMP
- So Ca++ levels are decreased, formation to protein kinase A is increased
- Myosin light chain is phosphorylated by protein kinase A
- Bringing about realxation of bronchi smooth muscle
What are the side effects of β2-adrenoceptors Agonists?
- Fine tremor
- Hypotension
- Tachycardia
What are two examples of cysteinyl leukotriene receptor (CysLT1) antangonists?
- Montelukast
- Zafirlukast
What are CysLT1 antagonists and mast cell stabilisers used to treat?
- Asthma
- Rhinitis
What is the mechanism of CysLT1 Antagonists?
(CysLT) are derived from mast cells
- Mast cells produce arachidonic acid through stimulating phospholipase A2
- FLAP enzyme stimulates 5-lopoxygenase
- Leukotrienes are released which bind to CysLT1
- CAUSES muscle contraction, mucus secretion and oedema
What do CYsLT1 antagonists prevent from binding?
Leukotrienes (cause inflammation)
What are the side effects of CysLT1 antagonitss and mast cell stabilisers?
- Abdominal Pain
- Headaches
“on a boat, the mast can hit you in the head or the stomach”
What are two examples of xanthines?
- Theophylline
- Aminophylline
What are xanthines used in the treatment of?
Asthma
What is the mechanism of xanthines?
- Inhibit phosphodiesterase (breaks down cAMP)
- Increase in cAMP levels
- Decreases protein kinase A
Give an example of an inhaled corticosteroid?
Beclometasone
Give an example of an oral corticosteroid?
Predinsolone
What are corticosteroids used in the treatment of?
- Asthma
- Rhinitis
When would oral corticosteroids be used in the case of asthma?
When it is very severe
What is the mechanism of action of corticosteroids?
- Signalling via nuclear receptors GRα, where glucocorticoid binds to GRα and enters nucleus
- Binds to promotor region
- Either produces transactivation or transrepression of genes
How do corticosteroids transactivate genes?
- Annexin-1 inhibits synthesis of phospholipase A1
- Decreases formation of arachidonic acid
- Decreases production of leukotrienes, chemotaxins and spasmogens
How do corticosteroids transrepress genes?
- Cytokines used to decrease formation of IL4,5,7 and 13
- Eosinophils and plasma cells (IgE are not recruited)
What are side effects of corticosteroids?
- Thrush
- Hoarse/weak voice
- Restricts growth
- Glaucoma
- Diabetes
- Cushing’s syndrome (weight gain, bruises, stretch marks)
What is cromoglicate used for?
- Allergic asthma
- Allergic rhinitis
What is omalizumab used for?
Allergic asthma
