L15 Clinical Pharmacology of Asthma

Ventilation occurs by contraction and relaxation of respiratory muscles, and the elastic ❌ of connective tissue in lungs. Any disease that ❌ elastic recoil can cause ventilation issues.
Obstructive diseases affect inspiratory rate (e.g. ❌), whereas restrictive diseases affect inspiratory capacity (e.g. ❌).

Choosing a selective drug helps to reduce on-target ❌. E.g. a Beta-2 agonist will have less effect on the heart than a ❌ Beta agonist.
If excessive doses are used then selectivity will be ❌ and the drug will act on other receptor subtypes. E.g. the usual inhaled dose of ❌ for acute asthma is 100 mcg, the dose used for severe asthma is 5 mg, 50 times more, and ❌ is expected.

Drugs for bronchodilation:
- Short acting beta agonists — ❌
- Long acting beta agonists — ❌
- Short acting muscarinic antagonists — ❌
- Long acting muscarinic antagonists — ❌

Side effects of bronchodilators for low dose beta agonists are an increased ❌ rate. Effects of high doses can include an increased heart rate, tremor, nervousness, peripheral ❌, sleep ❌, and decreased plasma ❌.
Side effects of muscarinic antagonists are an increased heart rate and a ❌ mouth.

Corticosteroid (anti-inflammatory) side effects:
— Inhaled low dose < ❌ mcg/day (budesonide equivalents) - ❌
— Inhaled high dose < ❌ mcg/day (budesonide equivalents) - oral candidiasis, growth ❌ (not certain, and minor, reversible), occasional HPA axis ❌
— Prednisone 5 mg/day, long term (>2 weeks) - ❌ symptoms.

Lung delivery from MDI:
≈ ❌ gets to the active locations in the lungs (bronchioles)
≈ ❌ deposits onto the oropharynx and can then reach the stomach and is absorbed
≈ ❌ either deposits to other areas or is exhaled