Respiratory Drugs

Question 1

Antihistamine (first gen)

Answer 1

UR drug
diphenhydramine, promethazine
- able to cross BBB
- side effects: affects CNS, lethargy, drowsiness, dizziness, fatigue, disturbed coordination, fall
- secondary use: insomnia, hallucination, seizure
- anticholinergic effects PNS
- PO/IV/IM

• contraindication: pregnancy, lactation, newborn, children, older adults, urinary retention/BPH, glaucoma, HTN

Question 2

Antihistamine (second gen)

Answer 2

UR drug
cetirizine, fexofenadine
- little to no sedative effect, little to no anticholinergic effect
- PO, nasal spray

Question 3

Decongestant (A1 agonist)

Answer 3

UR Drug
ephedrine, pseudoephedrine (nasal spray, mist, ophthalmic, IM, subQ, IV, PO)
- MOA: non-specific a and b agonist in large dose (PO and intranasal)
- a: peripheral vasoconstriction to decrease swelling, rhinorrhea
- a&b: worsening HTN, BPH, tachy
- CNS effects: restlessness, jittery, nervous

Question 4

Antitussive (cough lozenges)

Answer 4

UR drug

menthol: local anesthetic
- indication: dry cough for further irritation

Question 5

Antitussive (nonopioid)

Answer 5

UR drug
benzonatate (rx, PO soft gel), dextromethorphan (OTC syrup, lozenges)
- indication: dry cough for further irritation
- MOA: supresses the cough center in the medulla (no analgesic property)
- side effects: drowsiness, dizziness, euphoria with high dose

Question 6

Antitussive (opioid)

Answer 6

UR drug
codeine, in combination with antihistamine, decongestant, or expectorant
- MOA: suppress cough by increasing cough threshold in CNS (prodrug: have to be swallowed)
- side effects: drowsiness, resp depression, dizziness, nausea, constipation, hypotension, risk of abuse (reversed by naloxone)
- contraindication: resp disease, alcohol, head trauma

Question 7

Expectorant

Answer 7

UR drug
guaifensin (PO), dextromethorphan
- contraindication: never to children <4yo
- MOA: increasing respiratory tract fluid
- caution: drowsiness, dizziness

Question 8

Bronchodilators (B2 adrenergic agonist “terol”)

Answer 8

LR drug
rescue inhaler: albuterol, levalbuterol (MDI/neb) give first!
inhal/PO
- MOA: bronchodilation, dec. histamine, incr. ciliary motility
- side effects: B1 activation (tachy, dysrhythmia), nervousness, tremors, HA, inc BG
- avoid stimulants
- contraindicated: pregnancy, tachy, hyperthyroidism

Question 9

Bronchodilators (anticholinergic)

Answer 9

LR drugs

• MOA: anticholinergic –> bronchodilators
• everything is maintenance (opium)
• synergist effect when combined with b agonist
• contraindication: peanut allergy, glaucoma, BPH

Question 10

corticosteroids (glucocorticoids)

Answer 10

LR drugs

• route: IV/PO/Inha/nasal
• MOA: anti-inflammatory
• must always wean off
• • see study guide for depth**

Question 11

leukotriene modifiers

Answer 11

similar to antihistamine (montelukast)

• MOA: suppress the effect of LT, decrease inflammation, edema, mucus, bronchodilation
• indication: maintenance therapy
• side effects: depression, suicidal ideation, liver failure, drug interactions, consider age limits

Question 12

Mucolytic

Answer 12

acetylcysteine (inh/PO/IV)
- inhaled: mucolytic
- IV/PO: acetaminophen OD
- PO: prevent nephrotoxicity
MOA: breakdown protein structure of bronchiole secretions
- indication: CF, COPD, bronchitis 
- side effects: dizzy, drowsy, orthostatic hypotension, tachy, hepatotoxicity
- contraindication: children <7yo

Question 13

supplemental oxygen

Answer 13

• side effects: vasoconstriction, hypoxia leading to drive for CO2 retainers
• wean off