LECTURE 18: RESPIRATORY Flashcards
Respiratory system
comprises lungs and airways (trachea and bronchi)
respiration is controlled by
rhythmic discharges form medulla
asthma is
a non-communicable, long term inflammatory respiratory disease that causes narrowed airways and several symptoms
what kind of administration is used for asthma and why
inhalation for localised delivery
asthma attack consists of
acute phase (bronchospasm) and delayed phase (inflammation)
drugs in asthma are aiming to
relieve symptoms and prevent reoccurrence of attacks
two major categories of asthma drugs
bronchodilators and antiinflammatory
bronchodilators consists of
1) sympathomimemics
2) xanthines
3) anticholinergic
sympathomimemics
B agonists -> bronchodilation
sympathomimemic e.g.s
salbutamol, salmeterol, vilanterol
Xanthines
phosphodiesteras einhibitors -> increse cAMP leading to bronchodilation
xanhtine e.g.
theophylline
anticholinergic
muscarinic receptor antagonist
anticholinergic e.g.
ipratropium
antiinflammatory consits of
1) corticosteroid
2) leukotriene antagonists
3) cromolyn and nedocromil
4) omalizumab
corticosteroid
glucocorticoid binds to glucocorticoid receptor to up regulate expression of several anti-inflammatory proteins and down regulate pro-inflammatory proteins
corticosteroid e.g.s
prednisolone, fluticasone, cortisone
Leukotriene antagonists
drugs that inhibit the leukotriene pathway, an important inflammatory singalling pathway induced in airway smooth muscle contraction
Leukotriene drugs
- zileuton: inhibits 5-lipoxygenase to block formation of leokotriene
- montelukast: blocks cystLTI receptor, blocks leukotriene D4 action
Cromolyn and Nedocroomil
are mast cell stabilizers that prevent release of inflammatory mediators such as histamine
Omalizumab
binds to IgE and reduces binding to its receptors on the surface of basophils, mast cells and dendritic cells
limits degranulation of mast cells leading to decreased release of inflammatory mediators
allergic rhinitis
inflammation of the mucus membranes of the nose
treatment of allergic rhinitis
1) corticosteroid
2) cromolyn
3) nasal decongestants
4) antihistamines
nasal decongenstants
a1 agonsits
phenylephrine and pseudoephedrine
antihistamines
act of peripheral H1 histamine receptors to reduce symptoms of allergic rhinitis
allergic rhinitis antihistamine examples
antazoline and loralodine
COPD
group of related progressive illnesses that caause breathing issues and blocked airways
COPD e.g.
emphysema and chronic bronchitis
drugs used in COPD
bronchodilator and corticostroids
Cough
protective reflex that helps clear the airways of irritants, fluid or pathogen
should the cause of cough or the cough itself be treated
the cause, so may need antibiotics
cough drugs
1) dextromethorphan
2) codeine
3) pholcodine
dextromethorphan
suppresses cough reflex by binding to sigma receptors in the cough centre of brain (medulla)