Respiratory Pharmacology Flashcards
Drugs used in the respiratory system: Upper airways for…
allergy
Drugs used in the respiratory system: Lower airways for…
asthma, COPD
Drugs used in the respiratory system: Respiratory infection e.g for …
Bronchitis, Pneumonia, Atypical infection
Airway Drugs:
Bronchodilators (adrenergic agonists, anticholinergics, methylxanthines)
Anti-inflammatory (Steroids, leukotriene inhibitors)
Mucokinetic agents (Carbocysteine, hypertonic saline, dnase)
Give 2 examples of a beta-2 agonist
salbutamol, salmeterol
Name 2 anticholinergic bronchodilators
tiotropium, iprtratropium
Name 2 steroids
prednisolone, beclomethasone
Name a leukotriene inhibitor
monteleukast
Name 3 Mucokinetic agents (Airways)
carbocycsteine, hypertonic saline, Dnase
Inhaled Drug Devices
Metered dose inhalers (MDIs) = deep exhale/ inhale and puff/ hold breath for slow ten count/ exhale slowly/ wait one minute before second puff - use spacer
Dry-power inhalers - usually one inhalation, not a puff
Nebulisers
Multitude of new devices
Metered dose inhalers (MDIs) - how are they used?
deep exhale/ inhale and puff/ hold breath for slow ten count/ exhale slowly/ wait one minute before second puff - use spacer
Dry-power inhalers - how are they used?
one inhalation, not a puff
Salbutamol - short or long acting?
Short acting - begin immediately, 3-5 hour duration
Routes of Salbutamol
Inhaled/IV/Oral
Mechanism of Action of Salbutamol
Binding to beta(2)-receptors in the lungs results in relaxation of bronchial smooth muscles. It is believed that salbutamol increases cAMP production by activating adenylate cyclase, and the actions of salbutamol are mediated by cAMP
What conditions is salbutamol used in?
Asthma and COPD
Salmeterol - short or long acting?
Long acting (Begin 2-30 min, 10-12 hour duration)
Routes of Salmeterol
Inhaled
Mechanism of Action of Salmeterol
Long-acting-beta-adrenoceptor agonist
What conditions is salmeterol used in?
Asthma - in patients requiring long term regular bronchodilator therapy on ICS (not on its own)
NOT PRN
COPD: combination with LAMA or ICS eg. seretide
Tiotropium - short or long acting?
Long acting (24 hour)
Routes of Tiotropium
Inhaled (Dry powder Handihaler/Mist resimat)
Mechanism of Action of Tiotropium
Tiotropium is a long-acting, antimuscarinic agent, which is often referred to as an anticholinergic. Similar affinity to the subtypes of muscarinic receptors, M1 to M5. In the airways, it exhibits pharmacological effects through inhibition of M3-receptors at the smooth muscle leading to bronchodilation
Indication for Tiotropium
Stable COPD: Symptoms despite SABA (any severity)
Asthma: new indication step 3
Ipratropium - short or long acting?
Short acting antimuscarinic agent (onset 30 mins, lasts 6 hours)
Indication for Ipratropium
Nebulised for acute presentations of COPD (and sometimes asthma)
Theophylline half life
around 5 hours in healthy adults
Routes for Theophylline
IV/PO
Mechanism of action of Theophylline
Phosphodiesterase Inhibitor - acts indirectly to stimulate cAMP and bronchial smooth muscle relaxation
Indication for Theophylline
PO: COPD and asthma - persistent symptoms
IV: COPD and asthma - medical emergencies
Adverse Effects of Bronchodilators
Tachycardia Nervousness, Irritability, Tremor Inhaled preparations - less common Oral preparations - more common (tachyarrhythmias/angina) usually dose related
Adverse Effects of Bronchodilators are usually … related
dose related
Adverse Effects of Bronchodilators - more common in which preparations?
oral preparations
Glucocorticoids - Systemic (E.g. Prednisolone)
IV or oral
Stronger effects
action unaffected by lung restriction
More side effects, esp with long term therapy
Glucocorticoids - Inhaled (E.g. beclometasone)
Localized action
Fewer side effects: some absorption occurs
Disease may prevent penetration of drug to affected areas
Glucocorticoids are a class of …, which are a class of … hormones.
Glucocorticoids are a class of corticosteroids, which are a class of steroid hormones.
Airway effects of Glucocorticoids
Decrease release of inflammatory mediator
Decrease infiltration and action of WBCs
Decrease airway oedema
Decrease airway mucus production
Increase number and sensitivity of beta-2 receptors
Inhaled Steroids - adverse events
Oral candidiasis
Dysphonia
What is dysphonia?
Dysphonia refers to having an abnormal voice. It is also known as hoarseness.
General adverse events of steroids
Adrenal suppression, bone loss: exercise, Vit D, calcium, Slow growth in children but not ultimate height, increase risk of cataracts and glaucoma, increased risk of infection, gastric ulceration, hypertension, diabetes, mood disturbance
Medications for Allergic Rhinitis
Antihistamines - H1 antagonists, E.g cetirizine, chlorpheniramine
Intranasal Glucocorticoids - e.g. beclometasone (beconase)
Montelukast (Singulair) - inhibit leukotriene receptors, decreased inflammation, bronchoconstriction, oedema, mucus, recruitment of eosinophils
Sympathomimetics (Decongestants) - Pseudophedrine (alpha agonist) problems with abuse and MAOI
Asthma treatment ladder - how many steps?
5 steps - move up and down depending on symptoms and success of current drugs
Why do we have the asthma treatment ladder?
It is as important to move down the ladder as to move up, patients are often left on too much steroids
