drugs used in asthma Flashcards
is a heterogenous disease, usually characterized by chronic airway inflammation. it is defined by the history of respiratory symptoms such as wheeze, SOB, chest tightness, and cough that vary over time and in intensity, together with variable expiratory airflow limitation.
asthma
study this
in asthma patients there is a predominance of what cells that produces humoral response thereby stimulating plasma cells to produce IgE which attaches to Mast cells to produce a complex
TH2
____ secreted by plasma cells binds
the FcεRI receptor on submucosal mast cells and basophils and, when crosslinked by an antigen, induces the release of preformed mediators
such as histamine and leukotrienes, as well as the release of inflammatory cytokines.
Unbound IgE
These cells also migrate into the airway subepithelial mucosa, where they release inflammatory cytokines such as IL-5 and IL-13, which induce goblet cell metaplasia
and mucus production, and act as a chemokine for eosinophils, mast cells, and basophils
Th2
The histamine, tryptase, leukotrienes C4
and D4, and prostaglandin D2 released cause the smooth muscle contraction and vascular leakage responsible for the acute bronchoconstriction of the?
“early asthmatic response.”
“early asthmatic response” is
often followed in 3–6 hours by a second, more sustained phase of bronchoconstriction, the?
This late response is thought
to be due to cytokines characteristically produced by T2 lymphocytes, especially interleukins (IL) 5, 9, and 13.
“late asthmatic response,”
SYMPATHOMIMETIC AGENTS
Epinephrine, Ephedrine, Isoproterenol
Beta 2- selective drugs:
SABA:Albuterol, Terbutaline, Metaproterenol, Pirbuterol
LABA: Salmeterol, Formeterol
Ultra LABA: Indacaterol, Olodaterol, Vilanterol, Bambuterol
Methylxanthine drugs
Theophylline, Theobromine, Caffeine, Roflumilast (PDE4 inhibitor)
anti-muscarininc agents
SAMA: Ipatropium bromide
LAMA: Tiotropium, Aclidinium, Umeclidinium
CORTICOSTEROIDS
beclomethasone, budesonide, ciclesonide,
flunisolide, fluticasone, mometasone, and triamcinolone
LEUKOTRIENE PATHWAY INHIBITORS
zileuton, zafirlukast and montelukast
TARGETED (MONOCLONAL ANTIBODY)
THERAPY
Anti-IgE Monoclonal Antibodies: omalizumab
Anti-IL-5 Therapy:mepolizumab,reslizumab, benralizumab,Dupllumab
-are mainstays in the treatment of
asthma.
-Their binding to β-adrenergic receptors—abundant on
airway smooth muscle cells—stimulates adenylyl cyclase and increases the formation of intracellular cAMP thereby relaxing airway smooth muscle and inhibiting release
of bronchoconstricting mediators from mast cells
Adrenoceptor agonists/SYMPATHOMIMETIC AGENTS
is an effective, rapidly acting bronchodilator
when injected subcutaneously (0.4 mL of 1:1000 solution) or inhaled as a microaerosol from a pressurized canister (320 mcg per puff). Maximal bronchodilation is achieved within 15 minutes after inhalation and lasts 60–90 minutes.
Epinephrine
adverse effects of epinephrine
Because epinephrine
stimulates α and β1 as well as β2 receptors, tachycardia, arrhythmias, and worsening of angina pectoris are the serious adverse effects
used in China for more than 2000 years
before its introduction into Western medicine in 1924. Comparedwith epinephrine, ephedrine has a longer duration, oral activity, more pronounced central effects, and much lower potency.
Ephedrine
is a potent nonselective β1 and β2 bronchodilator.
When inhaled as a microaerosol from a pressurized canister,80–120 mcg isoproterenol causes maximal bronchodilationwithin 5 minutes and has a 60- to 90-minute duration of action.
Isoproterenol
They are effective after inhaled or oral administration
and have a longer duration of action than epinephrine
or isoproterenol.
Beta2-Selective Drugs
-Given by inhalation, these agents cause bronchodilation equivalent to that produced by isoproterenol. Bronchodilation is maximal within 15 minutes and persists for 3–4 hours.
-Nebulized therapy should
thus be reserved for patients unable to coordinate inhalation from a metered-dose inhaler
SABA: Albuterol, terbutaline, metaproterenol, and pirbuterol