Drugs Exam 5 Flashcards
Diphenhydramine (Benadryl) OTC
Class: first generation antihistamine
MOA: Blockade H1, muscarinic, alpha adrenergic, and 5HT receptors.
PK: well absorbed orally. Widely distributed including CNS.
Can be used as opthalmic solutions.
Side effects:
- Sedation (can potentiate other CNS depressants)
- Drying of secretions
- GI disturbances (N/V, diarrhea, constipation –> give w/ meals)
Acute poisoning treatment is symptomatic and supportive (dilated pupils, flushed face, fever, dry mouth, excitation, hallucinations, in-coordination, coma, CV collapse.)
Diphenydramine is specific for low incidence of GI side effects and causing sedation.
Uses: Allergy (rhinitis, urticaria, and atopic dermatitis),motion sickness, and sleep aid
Chlorpheniramine (OTC)
Most suitable first generation anithistamine for day time use
Cetrizine OTC
(Zyrtec)
Class: Second generation (non-sedating)
Only a small amount cross BBB. They are also actively effluxed by P-glycoprotein from the CNS.
MOA: inverse agonists and act as competitive inhibitors of histamine. No anticholinergic properties.
Therapeutic uses:
Allergy (rhinitis, urticaria, and atopic dermatitis),
Ibuprofen
Fewer GI side effects than aspirin.
Reversible COX inhibitor
Naproxen
Longer half life
Ketorolac
Given IV
Analgesia and anti-inflammatory
Ketopfofen
Related to Ibuprofen
Indomethacin
Most potent NSAID
Uses: Severe frontal headache and blood disorders. Also PDA
Piroxicam
Once a day administration, but can cause dose related serious GI bleeding.
Celecoxib
10-20x more selective for COX-2.
200mg/day
Acetaminophen
not an NSAID
Analgesic, antipyretic, but NOT antiinflammatory. Effectively inhibits COX in brain, but not in periphery.
OD can cause hepatic injury. Lower TI.
NSAIDs
Block COX 1 & COX 2 causing a decrease in prostaglandins, thromboxanes, and prostacyclins. Analgesic, antiinflammatory, antipyretic.
Platelets don’t have COX 2
Adverse effects: GI ulceration, prolongation of gestation, decreased renal function, increased bleeding time. hypersensitivity (Aspirin = 3-10% of asthmatics.
Acetylsalicylate (aspirin)
Irreversibly inhibits COX (8-10 days). Used in 81mg doses for heart patients.
Adverse effects: Reye’s syndorme (encpephalopathy, and fatty liver), hypersensitivity in 3-10% of asthmatics.
Zileuton
MOA: Inhibits the enzyme 5-lipoxygenase and thus prevents the synthesis of LTB4 as well as the peptide leukotrienes.
Decreases the use of beta-agonists.
Moderately effective in maintenance treatment of chronic asthma.
PK: metabolized by cyp 450
Toxicities: monitor for hepatic toxicity.
Zafirlukast
MOA: luekotriene receptor antagonoist (LTD4 receptor, Cys LTR1)
PK: inhibits CYP450.