Respiratory drugs Flashcards
SABA examples
salbutamol, terbutaline, albuterol
SABA main indications
first line treatment for mild intermittent asthma, COPD
mechanism of action of SABA
agonists of beta 2 adrenoceptors. causes bronchodilation and decreases mucous secretion
contraindications of SABA
use in caution with patients with arrhythmias, CVD, diabetes, hypertension, hyperthyroidism, hypokalaemia, and susceptibility to QT interval prolongation
adverse effects of SABA
tremor most common can also affect heart rhythm , oral thrush
LABA main indications
nocturnal asthma, COPD
LABA mechanism of action
agonists of beta2 adrenoceptor, always administered with an ICS
Contraindications of LABA
use with caution in patients with arrhythmias, CVD, hyperthyroidism, hypokalaemia, susceptibility to QT interval
adverse effects of LABA
beta 2 down regulation and tachyphylaxis with chronic use, may worsen asthma when used alone should always be given with ICS
Inhaled corticosteroids main indication
second line in asthma, consider for COPD where patient is a frequent exacerbator (2+ hopsital admissions a year) AND is eosinophilic (less than 300 cells/microlitre)
mechanism of action of ICS
synthetic derivatives of cortisol, anti inflammatory effect
Adverse effects of ICS
dysphonia and oropharyngeal candidiasis, pneumonia in COPD due to local immune suppression and impaired mucociliary clearance
Leukotriene receptor anatagonists main indication
add on in uncontrolled asthma (oral)
leukotriene receptor antagonist mechanism of action
prevent CysLTs from causing bronchoconstriction, mucus secretion, oedema
adverse effects of leukotriene receptor antagonists
generally well tolerated, headache, GI upset
Xanthines main indication
add on in uncontrolled asthma (theophylline oral), used in acute severe asthma attack (Iv aminophylline)
xanthines mechanism of action
inhibit mediator release of mast cells, increase mucus clearance, increase diaphragmatic contractility and reduce fatigue. prevent inactivation of cAMP and cGMP (they relax smooth muscle and are antiinflammatory)
xanthines contraindications
drug interactions involving CYP450s
adverse effects of xanthines
very narrow therapeutic index- adverse effects at supratherapeutic concentrations include dysrthmia, seizures and hypotension. at therapeutic conc can cause nausea, vomiting, headache
omalizumab
very expensive specialist treatment. injection every 2 -4 weeks. for asthma. anti IgE
mepolizumab/ benralizumab
very expensive specialist treatment. injection every 4-8 weeks. for asthma. targets cytokine that activates eosinophils. - IL5
dupilumab
very expensive specialist treatment. injection every 2 weeks. for asthma. blocks cytokines responsible for eosinophilic inflammation, IgE, airway hyper reactivity and mucin production
SAMA example
ipratropium
mechanism of action of SAMA
non selective m3 receptor antagonist- stops bronchoconstriction caused by M receptor activation in response to ACh. also reduces mucous secretion
