Respiratory Drugs and Pharmacology Flashcards
(50 cards)
What are 3 common Bronchodilator drugs?
Beta2 agonists (salbutamol/terbutaline)
Anticholinergic agents (ipatropium/glycopyrronium/tiotropoum)
Methylxanthines
(theophylline)
What are 4 common Anti Inflammatory agents?
Corticosteroids (fluticasone)
Disodium Cromoglycate
Sodium Nedocromil
Leukotriene Receptor Antagionists (LRTA) (e.g. Montelukast)
Give 2 antimicrobial agents?
Anti-bacterial drugs (antibiotics)
Anti fungal drugs (Rx od aspergillosis)
What agents can be used for humidification or secretion clearance?
Water and Saline.
Give 3 routes of delivery for Respiratory drugs/BD’s?
- Inhaled
- Oral
- IV
What does CSIT mean?
Continuous Subcutaneous Infusion of Terbutaline (CSIT)
What does CSIT do?
Improves Asthma Control
What can CSIT decrease?
- Less hospitalisation
- Less Corticosteroid Need
Who benefits most from CSIT?
Wide diurnal variability in PEF aka Brittle Asthmatics
Advantages of the Inhaled Route?
- Deliver directly to the large surface area of trachea-bronchial tree
- Therapeutic levels of drugs can be achieved locally with the bronchi leading to a more rapid onset of action
- Requires a lower dose of drug via oral route
- Lower incidence of side effects since systemic concentrations are lower
How do Bronchodilators work?
–> Bronchial smooth muscle contains both alpha and beta adrenergic receptors
–> If Beta receptors stimulated, mimic the activity of the sympathetic nervous system (-> dilation)
–> Beta 2 Agonists (Agonist - substance which initiates a physiological response when combined with a receptor)
Alpha adrenergic receptors causes
Smooth muscle contraction
Beta adrenergic receptors -
Smooth muscle relaxation
Where are Beta Receptors present?
In a high concentrations in lung tissue.
70% of Beta Receptors found in:
- Airway smooth muscle
- Epithelium
- Vascular Smooth Muscle
- Submucosal glands
Describe the density of Beta 2 receptors?
- The density in airway smooth muscle does not change at different airway levels
- Bronchioles have a similar density to large airways
- Beta agonists may bronchodilator all airways
Where are beta receptors localised to?
Submucosal Glands
- May lead to increase in mucus clearance
- Increase Ciliary Beat Frequency
What is the mode of action for beta 2 receptors?
1 -> Inhaled drugs stimulates Beta2 receptors in bronchial smooth muscle of obstructed airway
2-> Leads to activation of the enzyme adenyl cyclase
3-> Leads to increased production and elevation of cellular cyclic AMP in airway smooth muscle and mast cells
4-> AMP causes relaxation of smooth muscle by decreased Ca
5-> Increased cAMP inhibits release of bronchoconstrictor mediators from mast cells such as histamine and leukotrienes
6-> Leads to bronchodilation
What is the onset for SABA’s?
1-2 minutes
When is maximal effect of a SABA?
20 mins after having it
How long does bronchodilation last?
3-6 hours
How long do Long acting stimulants last?
12 hours such as Salmeterol
Indications such as OLC?
Asthma
COPD
List Side Effects (4)
1 - Skeletal muscle tremor
2- Tachycardia
3-Metabolic changes (Hypokalaemia and HyperGlycaemia)
4-Cardiac Arrythmia
Contraindications?
- Hypersensitivity to drug
- Pregnancy/Breast feeding
- Tachyarrhythmia
- Children aged 2 or below
- Signed referral from HCP
