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Flashcards in 2 - Respiratory Pharmacology Deck (41):

What are the 3 types of nasal decongestants?

  1. Direct alpha adrenergic stimulants
  2. Mixed function adrenergic stimulants
  3. Orally administered


What is the mechanism for direct alpha adrenergic stimulants?

  • Vasocontriction to reduce edema
  • Decrease bloodflow to tissues in nose, which decrease tissue volume, making it easier to breathe


What are the preparations of direct alpha adrenergic stimulants?

  • Nasal spray
  • Vasoconstrictors:
    • propylhexedrine (Benzedrex - OTC)
    • oxymetazoline (Afrin
    • tetrahydrozoline (Visine) 
    • naphazoline ("Clear Eyes")


Why is Afrin limited use to only 3 days?

Addictive: it crosses the BBB


What is the side effects of direct alpha adrenergic stimulants?

  • Increased peripheral resistance
  • Bradycardia
  • Rebound congestion with extended use


What is the mechanism of Mixed function adrenergic stimulants?

  • Alpha and beta stimulation, direct and indirect effects (sympathomimetic)


What are the preparations of mixed function adrenergic stimulants?

  • ephedrine - releases tissue stores of epinephrine, thus stimulates alpha and beta receptors
    • Crosses BBB and causes CNS excitation, bronchial dilation / relaxation
  • phenylephrine (Neo-Synephrine)


What is the mechanism of orally administered direct-acting alpha and beta agonists (sympatheticomimetic)?

  • Directly stimulates alpha receptors of respiratory mucosa causing vasoconstriction
  • Directly stimulates beta receptors causing bronchial relaxation
  • Works systemically, not locally


What is the common preparations of orally administered direct-acting alpha and beta agonists?

  • pseudoephedrine (Sudafed, Actifed)


When a patient is taking decongestants, what must be given with caution and why?

  • epinephrine (vasoconstrictor)
  • These drugs are sympathomimetics and may enhance cardiac stimulation (tachycardia) and elevate blood pressure


What does the antigen-antibody response of bronchial asthma cause to be released?

  • Histamine - vasodilation and edema, bronchoconstriction
  • PGD2 - bronchoconstriction, inflammation
  • LTC4/LTD4 - urticaria/angiodema, mucosal edema, smooth muscle spasm, attracts eosinophils


What are the main symptoms of bronchial asthma?

  • Functional increase in airway resistance and decrease in lung compliance
  • Inflammation, mucous secretions, spasm of airway


What are medications that can trigger asthma?

  • Aspirin - bronchoconstriction in 10% of pts with asthma
  • Antihypertensives - beta blockers, ACE inhibitors
  • Sulfites (preservatives) - found in dental local anesthetics that contain epinephrine to prevent oxidation of vasoconstrictor


What is the basic principle behind using medications to treat asthma?

  • Many beta adrenergic drugs block phosphodiesterase which increases tissue concentrations of cAMP
  • Which promotes catecholamine stimulation and epinephrine release from adrenal medulla = this accounts for their cardiac side effects
  • Increased cAMP in inlammatory cells decrease release of autocoids = desired effect
  • Tradeoff: bronchodilation but with adverse cardiac events


What is the mechanism of epinephrine?

Increases cAMP in inflammatory cells which reduce autocoid release


How can the action of epinephrine be blocked?

By propranolol (Inderal), a non-selective beta blocker used as an antihypertensive


What is the important rescue drug for asthma?

Inhalers - reversal of airway obstruction and bronchoconstriction; acute treatment of bronchospasm "asthma attack"


What is the mechanism for inhalers?

Target beta 2 receptors in airway, resulting in bronchodilation


What are the short acting beta adrenergic stimulants (rescue drugs)?

  • albuterol (Proventil, Ventolin) - in all dental office emergeny kits
  • levalbuterol (Xopenex) - R enantiomer of albuterol
  • metaproterenol (Alupent)
  • pirbuterol (Maxair)
  • terbutaline (Brethaire)


What are the long-acting beta adrenergice stimulants (maintenance/prevention)?

  • salmeterol (Serevent Diskus) - duration to 12 hours
  • salmeterol with fluticasone (steroid) (Advair Diskus)


What are some important dental considerations with inhalers?

  • Taste alteration
  • Oral candidiasis (with combined steriods)
  • Overuse of inhalers can lead to a hyper reflexive airway 
  • Have pts bring inhalers with them


Why ask your patients about how often they are using their inhalers?

If its more than once daily or 2 days per week it suggests uncontrolled asthma = REFER


What type of drug are methylxanthines?

Beta Adrenergic Stimulants

Older class of asthma drugs that are now typically thought of as reserve drugs, used for patients for whom newer, better asthma meds are ineffective. 


Why are xanthines considered "red flag" drugs?

  • Cause dangerous drug interactions resulting in CNS stimulation and increased risk for seizures
    • Antibiotics: macrolides 
    • Systemic (azole) antifungals - ketoconazole


What type of drugs block phosphodiesterase which increases cAMP?



What's the preparations of methylxanthines?

  • theophylline (Elixophyllin, Theochron, Theo-24)


What are the drugs of choice for reducing inflammation?



What are steroids mechanism of action?

  • Reduce cytokine production
  • Inhibition of accumulation of basophils, eosinophils and leukocytes


What are dental considerations of steroids?

  • Oral candidiasis
  • Susceptibility to infection
  • Delayed wound healing
  • Adrenal suppression


What is acetylcysteine (Mucomyst) and what does it do?


Exerts mucolytic action through its free sulhydryl group = opens up disulfide bonds in mucoproteins, thus lowering mucous viscosity


What drug is used for chronic bronchopulmonary diseases and cystic fibrosis?

Mucolytics - acetylcysteine (Mucomyst),


dornase alfa (Pulmozyme) just for CF


What drug is a DNA enzyme (recombinant) which cleaves DNA, reducing mucous viscosity?

dornase alfa (Pulmozyme) for cystic fibrosis


What are expectorants mechanism of action and what's the common prep?

Irritation of stomach while stimulating respiratory fluid volume, decreases mucous viscosity 

guaifenesin (Mucinex, Robitussin)


What type of drugs depress cough center in medulla?

Anti-tussive drugs


What is a common prep of an anti-tussive drug?

dextromethorphan (Delsym, Robitussin, Triaminic, Vicks 44)

Relative of morphine, lacking narcotic properties except in overdose


What type of drug is codeine?

D,L racemic mixture form of codeine will be anti-tussive, but also addictive, D form is less


Of the Leukotriene drugs, which drug inhibits the synthesis of leukotriens and which one blocks luekotriene receptors?

  • zileutron (Zyflo) = inhibits synthesis
  • zafirlukast (Accolate) & montelukast (Singulair) = blocks leukotriene receptors


What type of drugs are used for prevention of seasonal allergies and exercise-induced asthma? And what are the common preps?

Mast cell inhibitors

  • cromolyn (Nasalcrom - OTC)
  • nedocromil (Tilade) - inhaled only


What is the drug of choice for emphysema? And what's it's mechanism?

Anticholinergic medication

ipratropium (Atrovent)

Blocks action of acetylcholine at parasympathetic sites in bronchial smooth muscle causing bronchodilation


What's the mechanism for respiratory depressants?

Decreases sensitivity to increased PCO2 levels and to hypoxic drive

Narcotics, barbiturates, ethanol overdose


What's a common prep for a respiratory stimulant?

doxapram (Dopram)