Regal Drugs Flashcards
Mediator that causes redness, heat, swelling and airway constriction but not chemotaxis.
Histamine
Vasodilate, increase vascular permeability and cause pain
PGE2 and PGI2
What two things cause bronchoconstriction?
PGD2 and thromboxane
What causes platelet aggregation?
TXA2
What opposes platelet aggregation?
PGI2
Kinins (bradykinin and kallidin) are very strong what?
Vasodilator!
Which way do antihistamines shift the agonist dose-response curve?
Right (competitive antagonist)
Which histamine receptor is responsible for most clinically relevant symptoms like bronchoconstriction, contraction of GI smooth muscle, increased capillary permeability (wheal), pruritis and pain, and release of catecholamines?
H1 receptor
Describe how old antihistamines (classical, first generation antihistamines) work.
Block H1, Muscarinic, alpha adrenergic, and serotonin receptors, widely distributed (including CNS), not recognized by p-glycoprotein.
Side effects: Sedation, drying of secretions (due to anticholinergic properties), GI disturbances
Name the 2 first gen antihistamines we need to know and when to use them.
Diphenydramine (good for sedation) and Chlorpheniramine (suitable for daytime).
How are the newer antihistamines different than the first generation ones?
Minimal anticholinergic properties, DO NOT cause sedation
Which newer antihistamines do we need to know?
Cetirizine, Fexofenadine, Loratadine
Why don’t the newer antihistamines cause sedation?
B/c pumped out of CNS as they have a high affinity for p-glycoprotein.
Why were the new antihistamines created?
B/c original had cardiotoxicity with overdosage.
Which COX is constitutively expressed in most cells, protects gastric mucosa, and is found in platelets?
COX-1
COX-2
NOT in platelets, induced by serum factors, cytokines, and growth factors!
What causes pain?
Prostaglandins
Which drugs inhibit COX-1 and COX-2? What are their shared therapeutic activities?
NSAIDs: ANALGESIA: pain of low to moderate intensity, no addiction, lower maximal effects than opioids, block prostaglandin synthesis, ANTIPYRETICS: reduce body temp, ANTI-INFLAMMATORY-reduce redness, swelling, heat, and pain.
Which drugs are NSAIDs?
Aspirin (irreversible) Ibuprofen Naproxen Ketorolac (promoted for analgesia) Ketoprofen Indomethacin (most potent, severe frontal headache, blood disorders) Sulindac Piroxicam (can cause dose-related GI bleeding)
What selective COX-2 Inhibitor is still on the market?
Celecoxib
What drug is analgesic, antipyretic, NOT anti-inflammatory, and is not an NSAID? (also overdosage can cause serious hepatic injury).
Acetaminophen
Why is acetaminophen better than NSAIDs for headaches?
Because it inhibits COX in the brain but not at sites of inflammation.
What is the only drug that irreversibly inhibits COX1 in the platelet (preventing aggregation and TX formation)?
Aspirin
What are the symptoms and what is the cause of aspirin hypersensitivity?
Rhinitis, urticaria, asthma, and laryngeal edema.
Blockade of COX shifts arachidonic acid utilization to the lipoxygenase pathway. The end result is increased leukotriene production and the symptoms of hypersensitivity.
