Respiratory Drugs (Trachte) - W3 Flashcards
Sympathetic receptors
- Nicotinic
- Alpha1
- Beta2
Parasympathetic receptors
- nicotinic
- muscarinic
How does the nicotinic receptor work? What binds? location?
- located on adrenal medulla
- causes activation of medulla by acting as pore for sodium –> releases epinephrine.
What is a nicotine agonist used for smoking cessation?
Varenicline (Chantix)
What stimulates the alpha1 receptor? How does it work? Where is it found?
- stimulated by epi=NE >> isoproterenol
- stimulates phospholipase C –> generates inositol triphosphate –> elevates caclium concentrations –> contraction of vascular smooth muscle
- NOT ON BRONCHIOLES
- majorly acts on vasculature (contraction)
What stimulates the beta2 receptor?
What does it do?
-
isoproterenol > epi >> NE
- NE not very effective
- works to RELAX SMOOTH MUSCLE of bronchioles
- activates adenyly cyclase –> glycogenolysis
- cholera toxin works through it (GS-alpha)
What are 2 nicotinic antagonists?
Trimethaphan & Hexamethonium
Stimulators of NE release from the sympathetic system:
Tyramine
Amphetamine
Ephedrine
Metaraminol
Inhibitors of NE release from sympathetic system
Reserpine
Guanethidine
Stimulators of sypmathetic on effect organ (NE effect)
- NE
- Epinephrine
- isoproterenol
- ephedrine
- phenylephrine
- metaraminol
Inhibitors of sympathetic effect on effector organ:
- Phentolamine
- Phenoxybenzamine
- propranalol
What do parasympathetic receptors tend to cause?
contract smooth muscle!! (except in vasculature)
Primary constrictor of the vasculature:
alpha1 receptor (how decongestants work)
primary dilator of bronchioles:
B2 receptor via sympathetics (epinephrine)
Primary bronchiole constrictor and cause secretion
parasympathetic muscarinic receptors
What is the most effective therapy for ACUTE BRONCHOSPASM?
list some.
- B2 agonists
- metaproterenol - inhaled
- terbutaline
- albuterol
- Pirbuterol
- isotharine
What are the long duration B2 agonists?
- Salmeterol - inhalation - more fat solube sto sticks around membrane and has longer duration of action.
- Formoterol
- Arformoterol
What are the major side effects of B2 agonists and what receptors do they act through?
- tachcardia - B1
- palpitations - B1
- tremor - B2
- headache
Epinephrine
mechanism
metabolism
contraindications
use
- relax bronchioles (parental for anaphylaxis, ocular or inhaled)
- metabolized by MAO and COMT
- contraindications: hyperthyroidism, hypertension, halogen-hydrocarbon anesthetics.
- Use:
- bronchospasm (B2) - not asthma
- hypersensitivity reactions
Why may you give corticosteroids with asthma?
they upregulate B2 receptors
Isoproterenol
use
administration
metabolism
- relax bronchioles via B2
- used w/respiratory disease.
- parental or aerosol
- metabolized by COMT
How does ephedrine work?
- releases NE and has direct effects
- constricts vessels –> reduces stuffiness and secretions
- increases BP
- relaxes bronchioles
What is ephedrine used for?
- bronchospasm
- allergy
- narcolepsy
- Stokes-Adams syndrome (in medications for colds)
what is pseudoephedrine
Sudafed - used similar to ephedrine (just a stereoisomer)
What is an alpha1 agonist and what is it used for?
phenylephrine - used as a decongestant by constricting vasculature
What are 2 muscarinic receptor ANTAGONISTS?
What are they used for?
- Ipratropium - bronchodilator 4x/day
- Tiotropium - longer acting 1x/day
Used for COPD. May also reduce secretion due to sympathetic stimulation.
What are 2 ways to increase cGMP?
- NO acting through receptor to stimulate guanylate cyclase
- ANP
What is roflumilast? What is it used for?
- phosphodiesterase 4 inhibitor
- used for bronchodilation w/COPD
- improves FEV1
- nausea is AE.
How is COPD distinguished from asthma?
Asthma = reversible.
COPD = not reversible.
What drugs cause mucosal stuffiness
- alpha blockers
- Phentolamine
- Phenoxybenzamine
- prazosin
- terazosin - used for prostatic hypertrophy to ease urination
What drugs increase airway resistance?
-
beta blockers
- propranolol
- timolol
- pindolol
- labetalol (alpha1 and beta)
- metoprolol
- atenolol
- esmolol
What is an example of a muscarinic agonist?
Bethanecol
What two things could cause mucosal congestion (drug classes)
- alpha 1 antagonists
- NE depleting agents (like guanethidine)
What is a common side effect of lisinopril? Why?
Cough and angioedema
Bradykinin isn’t inactivated (builds up)
What is an anticholinesterase that can cause bronchoconstriction?
neostigmine
physostigmine
pyridostigmine
edrophonium
ecothiophate
parathion
malathion
soman
chlorpyritos
