Respiratory Drugs Flashcards
(27 cards)
What is the mechanism of action of salbutamol?
It stimulates B2 receptors in the airways generating intracellular cAMP
⬇️ intracellular calcium = bronchodilation
Prevents mast cell degranulation
(Inhibits uterine smooth muscle contraction in premature labour)
What are the indications for prescribing salbutamol?
Asthma
COPD (with reversible component)
Premature labour
What are the contra-indications for prescribing salbutamol?
Hyperthyroidism
Cardiovascular disease
Arrhythmias (susceptibility QT interval prolongation)
Hypertension
What are the possible side-effects of salbutamol?
Common: tremor, tachycardia,
Rare: headache, palpitations, hypokalaemia, muscle cramps and insomnia
What are the interactions of salbutamol?
Corticosteroids: high dose of both drugs ⬆️ risk of hypokalaemia
Loop/thiazide diuretic: ⬆️ risk of hypokalaemia
Theophylline: ⬆️ risk of hypokalaemia
What class of drug ipratropium bromide?
Anticholinergic
Antimuscarinic bronchodilator
What is the mechanism of action of ipratropium bromide?
Bronchodilation by competitively inhibiting acetylcholine mediated bronchoconstriction and mucus secretion
What are the indications for using ipratropium bromide?
Reversible airway obstruction (asthma COPD)
Rhinitis
What are the cautions of ipratropium bromide?
Prostatic hyperplasia
Bladder outflow obstruction
Pts at risk of glaucoma
What are the possible side-effects of ipratropium bromide?
Dry mouth nausea Headache Constipation Tachycardia Palpitations Urinary retention
What are the possible interactions with ipratropium bromide?
Avoid with clarithromycin/erythromycin
Increase risk of side effects with antidepressants
Decreased effect of sublingual nitrates (due to dry mouth)
What class of drug is prednisolone?
Corticosteroid
What is the mechanism of action of prednisolone?
- inhibits phispholipase A2 activity = ⬇️ arachidonic acid production
- arachidonic acid = precursor for prostaglandin and leukotriene synthesis = anti-inflammatory effect
- ⬇️ B and T lymphocyte response to antigens = immunosuppressive effect
What are the indications for prednisolone?
Suppression of allergic/inflammatory disorders IBD Asthma Rheumatoid disease Immunosuppression
What are the contra-indications of prednisolone?
Systemic infection Hypersensitivity Osteoporosis Glaucoma Administration of live vaccines
What are the cautions of giving prednisolone?
Recent MI
Pregnancy
What are the potential side-effects of giving prednisolone?
Common: bruising, hirsutism, moon-face, hypertension, weight gain/oedema, impaired glucose tolerance
Rare: mood changes, muscle weakness, TB reactiviation
What interacts with prednisolone?
Phenytoin: ⬇️ effect of prednisolone
Rifampicin: ⬇️ effect of prednisolone
What class of drug is beclometasone?
An anti asthmatic corticosteroid
What is the mechanism of action of beclometasone?
Reduces hyper-reactivity and decreases activation of inflammatory cells and the release of mediators especially cytokines
What are the indications for using beclometasone?
If bronchodilator therapy is inadequate in asthmatics
Acute severe asthma attack
What are the side-effects of beclometasone?
Regular high doses of inhaled corticosteroids can be absorbed and cause adrenal suppression
Hoarse voice
Oral candidiasis
What class of drug is oxygen?
Therapeutic gas
What is the mechanism of action of oxygen?
Specifically binds to Hb and dissolves on plasma
Transported to tissues and promotes aerobic respiration
