- Created by: MazzaW
- Created on: 03-12-19 17:21
1. SABA (consider stepping up is using 3+ times/week)
2. Add low dose ICS
3. Initial add-on therapy: LABA
4. Additional controller therapies: increase ICS dose or add leukotriene receptor antagonist. If no response to LABA, consider stopping it
5. Regular oral corticosteroid (prednisolone). Refer patient for specialist care
Aims of mgmt = control of the disease. Complete control is defined as: no daytime Sx, no nighttime awakening due to asthma, no need for rescue medication, no asthma attacks, no limitations on activity (including exercise), normal lung function (in practical terms, FEV1 and PEFR > 80% predicted or best), minimal side effects from medication
Short acting beta-agonist e.g. salbutamol. Acts on adrenergic receptor to causesmooth muscle relaxation
1st line for all new asthma Dx. If being used 3+ times/week, consider stepping up treatment.
Acute bronchodilator effect, onset 5-30 mins, relief for 4-6hrs
Routs: inhalation of aerosol(MDI)/powder/nebulised solution, oral (tablet/solution), parenteral (IV/SC/IM injection)
Side effects minimised by inhaled delivery instead on systemic.
S/E: fine tremor, anxiety, headache, muscle cramps, palpitations, hypokalaemia, tachycardia, arrhythmias, peripheral vasodilation, myocardial ischaemia, sleep/behavioural disturbance
Long acting beta agonist e.g. salmeterol, formoterol
Chemical analogue on salbutamol with long lipophilic side-chain that anchors it in the lipid membrane to allow active portion to remain at receptor site- longer effect
Slower onset so not for use in relief of acute asthma attack
Acts on adrenergic receptor to cause smooth muscle relaxation
S/E: fine tremor, anxiety, headache, muscle cramps, palpitations, hypokalaemia, tachycardia, peripheral vasodilation, arrhythmias, myocardial ischaemia, sleep/behavioural disturbances
Long/short acting muscarinic antagonists e.g. ipratropium (SAMA), tiotropium (LAMA)
2nd line drugs (alternative/addition). Antagonise endogenous Ach at muscarinic (M3) receptors to relax bronchial smooth muscle and reduce mucus production
Useful in patients unable to take beta agonists (patients with IHD/tachycardia)
Generally reserved as an adjunct in acute severe asthma
Anticholinergic S/E: dry mouth, blurred vision, dizziness, tachycardia, hot flushed skin, agitation, urinary retention, constipation, delirium
2nd line drug (alternative/addition)
Inhibits phosphodiesterase so increases cAMP in smooth muscle cells -> activates PKA -> inhibits TNFa and leukotriene synthesis. Also reduces inflammation and innate immunity, and reverses steroid insensitivity.
Causes acute bronchodilation, may inhibit delayed phase reaction.
Usually administered orally for sustained release.
Narrow therapeutic index. Clarithromycin and ciprofloxacin inhibit metabolism so increase levels of theophylline.
Adverse effects: nausea, diarrhoea, tachycardia, headaches, insomnia, irritability, dizziness, arrhythmias
Leukotriene receptor antagonists
Inhibit cysteinyl L1 receptor - only 1 pathway involved in asthma so less effective than steroids but also less side effects
Available orally (tablets)
Extensively metabolised- metabolites undergo biliary excretion.
Good for prophylaxis but not effective in acute asthma attacks
Inhibit phospholipase A2 and cyclooxygenase (both pathways involved in asthma)
Decrease inflammation and mucus production.
Usually inhaled, can give oral corticosteroids in acute attacks
Adverse effects: oral candidiasis, hoarseness, easy bruising, wt gain, increased appetite, osteoporosis, iatrogenic adrenal suppression, gastritis/GI bleeds, cataracts, mood changes, sleep disturbance, insulin resistance/impaired glucose handling/diabetes
IgE monoclonal antibodies
Only used by specialist respiratory physicians in severe persistent confirmed IgE-mediated asthma needing continuous/frequent oral steroids (4+ courses/yr)