Respiratory Drugs Flashcards
Which classes of drugs cause low potassium?
Corticosteroids, beta 2 agonists, methylxanthines (aminophylline)
Which drugs cause tachycardia?
Beta 2 agonist, methylxanthines (theophylline)- come from caffeine
Which classes cause hyperglycaemia in a diabetic patient?
Corticosteroids, beta 2 agonists
Which drugs cause psychiatric side effects?
Corticosteroids, leukotriene receptor antagonist
Which class causes osteoporosis?
Corticosteroids
How do selective beta2 agonists work?
Stimulate b2 adrenoreceptors and cause adenyl cyclase to convert ATP to cAMP which activate a protein kinase
This inhibits myosin light chain kinase inhibits smooth muscle contraction resulting in bronchial smooth muscle relaxation
What is different in dosing of inhaled and nebuliser?
Inhaled 100mcg, nebuliser 2.5mg
How does aminophylline work?
Inhibits phosphodiesterase which breaks down CAMP into AMP, therefore more protein kinase A
What are side effects of SABA?
Fine tremor, resting sinus tachycardia, hypokalaemia
SABA onset and duration?
5 minutes, last 4-6 hours
Onset of action of LABA?
15-45 mins, Formoterol
How do antimuscarinics work?
Bind to muscarinic receptors in bronchial smooth muscle (mainly M2/M3), cause bronchodilator
Tiotropium - selective to m3 due to slow dissociation
What should not be prescribed concurrently?
LAMA inhaler, and SAMA-
SAMA onset and duration?
Onset 30 mins, 3-5 hours
Dose of SAMA?
Nebuliser 500mcg QDS, inhaler 20mcg QDS
When using a nebuliser ipratropium what should you be cautious of?
Narrow angle glaucoma due to increased risk of intraocular pressure
Side effects of antimuscarinics?
Dry mouth, dry eyes, headache constipation
First line for COPD?
LABA/LAMA
Asthma treatment with?
LAMA + ICS/LABA
Tiotropium onset duration?
2 hours onset, lasts 24 hours
Which is the only LAMA licensed for COPD and asthma?
Respiratory 2.5mcg inhale 2 puffs in the morning
How do corticosteroids work in asthma?
Decrease formation of stroking skin which activate eosinophils and are responsible for promoting production of IgE
Inhibit COX2 induction- antinflammatory
Inhibit leukotrienes, which would trigger contraction in smooth muscles
Side effects of corticosteroids?
Oral candidiasis, hoarse voice,
LAMA/LABA and ICS are for?
COPD patients with asthmatic features suggesting steroid responsiveness who remain breathless or have exacerbation on LABA/LAMA
MDI vs DPI?
MDI- slow/ steady
DPI- quick and deep
Acute attack of asthma/COPD?
Asthma- pred 40- 5 days
COPD- Pred 30 for 5-7 days
Theophylline is metabolised by?
Cytochrome P450, clearance declines with age/comorbidities
Smoking cessation …?
Increases serum theophylline
Theophylline level and monitoring?
10-20mg/l
Oral: 4-6 hours after dose then 5 days later
IV: take 6 hours after infusion, then once daily
Drug interactions with theophylline?
Metabolised by CYP1A2
So enzyme inhibitors such as macrolides, ciprofloxacin will increase levels
Enzyme inducers such as rifampicin/ ritonavir will decrease levels
Side effects of theophylline?
Headache, insomnia, nausea,
hypokalaemia,
Toxicity: vomiting nausea, tachycardia, ventricular arrhythmia and convulsions
HINT hypokalamia
Mucolytics are used in?
COPD, severe pneumonia, Cystic Fibrosis, bronchiectasis
carbociterine, acetylcysteine, may report itching
How do leukotrienes work?
Released from mast cells and eosinophils and cause bronchoconstriction and inflammation
LTRA work by?
Binding to LT receptors, and airway macrophages and eosinophils blocking bronchoconstriction and mucous secretion
Side effects of LTRA?
Neuropsychiatric side effects, headaches, GI
If hospital stays within 2 weeks treat as?
HAP
Nicotine withdrawal can cause?
Insomnia, irritability, anxiety craving
Craving satisfaction?
Dual NRT- long acting OD patch plus 1 short acting PRN
Nicotine partial agonist, drug to help smoking?
Varenicline
Asthma guideline?
- SABA + ICS
- ICS + LABA
- increase ICS to moderate or add LTRA
Refer to specialist
When to consider stepping up treatment?
Increased frequency attacks
x3 or more inhaled b2 agonist
Symptomatic x3 or more
Waking one night a week
Asthmatic specialist treatment?
Tiotropium respimat
Long term PO corticosteroids
MAB= mepolizumab- eosinophilia asthma
Omalizumab- severe allergic asthma
Specialist COPD drug roflumilast?
Phosphodiesterase 4 inhibitor