exam 5 antihistamines, decongestants, etc etc etc

an increase in histamine causes...

vasodilation, capillary leakage, bronchoconstriction

H1 blockers treat...

allergic rhinitis, anaphylaxis, angioedema, insect bites, pruritis

antihistamine drugs

diphenhydramine

chloropheniramine

fexofenadine

loratadine

cetirizine

antihistamine MOA

bind to the histamine receptors, preventing histamine response. they do not knock off the histamines that are already bound to receptor

antihistamine indications

allergic rhinitis, seasonal allergies, common cold, Parkinson's (anticholinergic), sleep aid

antihistamine contras

asthma attack (useless), narrow angle glaucoma (pressure), coronary artery disease, respiratory diseases, seizure disorders, urine flow disorders (BPH, pressure), elderly pts (paradoxical effects)

antihistamine adverse effects

drowsiness, anticholinergic effects

antihistamine interactions

allergy testing (stop 4 days prior), ETOH, MAOIs, other CNS depressants (additive effects), other anticholinergics

decongestant drugs

oxymetazoline

ephedrine

phenylephrine

pseudoephedrine

beclomethasone

budesonide

fluticasone

decongestant MOA

adrenergic: vasoconstriction

anticholinergic: drying effects

inhaled steroids: deal with immune response, suppress immune system

decongestant indications

common cold, allergies, allergic rhinitis, sinus surgery (easier to view mucosa)

decongestant contras

adrenergic: narrow angle glaucoma, uncontrolled CV disease, HTN, DM, hyperthyroidism

inhaled: sinus infection

decongestant adverse effects

nervousness, insomnia, palpitations, tremor, dry nose/mouth, usually well tolerated

decongestant interactions

other adrenergic drugs (increase SNS stim.), MAOIs

decongestant implications

encourage fluids to decrease drying, rinse mouth after inhaled steroid administration to avoid thrush, goal of tx is to have less nasal stuffiness, watch for rebound stuffiness

antitussive drugs

opioid: codeine, hydrocodone

non-opioid: dextromethorphan, benzonatate

antitussive MOA

opioids + dextromethorphan: suppress cough by direct action on medulla

benzonatate: anesthetizes the stretch receptors in respiratory tract, prevents reflex stim.

antitussive contras

opioid: risk of addiction, CNS depression, urinary retention

benzonatate: productive cough

dextromethorphan:

hyperthyroidism, CV disease, HTN, glaucoma

antitussive indications

cough!

antitussive adverse effects

sedation, GI issues, dizziness

antitussive interactions

opioids: general anesthesia, tranquilizers, sedatives, hypnotics, tricyclic antidepressants, ETOH, other CNS depressants

expectorant drugs

guaifenisen

expectorant MOA

increases hydration in respiratory tract to break up secretions

expectorant indications

situation where pt needs to cough up secretions

expectorant contra

drug allergy

expectorant adverse effects

GI upset (encourage fluids to resolve)

antihistamine implications

don't give during acute asthma attack, take with food, manage dry mouth, don't mix with other OTC cold meds unless ordered, watch for paradoxical effects with elderly

antitussive implications

fall prevention due to drowsiness, caution with opioids due to CNS depression and abuse, give at intervals to establish steady state