H1/H2/PPI (Ex1) Flashcards
Histamine released from
Endogenous
-From basophils and mast cells
Histamine significant effects (2)
-Contraction of Airway Smooth muscle
-Secretion of stomach acid
Significant drugs that release histamine (5)
Morphine
Mivacurium
Atracurium
Succinylcholine
Protamine
H1 receptor effects (3)
-Hyperalgesia
-Inflammatory pain
-Allergic rhino-conjunctivitis symptoms
H2 receptor effects (2)
-Elevates cAMP (B1-like stimulation)
-Increase acid volume
Histamine inflammatory effects (H1 and H2) (5)
Hypotension
Capillary permeability
Flushing
Prostacyclin release
Tachycardia
H1 receptor antagonist side effects (4)
Blurred vision
Urinary retention
Dry mouth
Drowsiness (1st gen)
First gen H1 antagonist drugs (2)
Diphenhydramine (Benadryl)
Promethazine (Phenergan)
Second gen H1 antagonists (2)
Cetirizine (Zyrtec)
Loratadine (Claritin)
Diphenhydramine trade name
Benadryl
Benadryl main uses (3)
-Antipuritic
-Pre-treatment for allergies (IVP dye)
-Anaphylactic indications
Benadryl E 1/2 time
7-12 hrs
Benadryl benefit in eye surgery
Inhibition of oculo-emetic reflex
Benadryl dose
25-50 mg IV
Phenergan main use
Rescue anti-emetic
Phenergan E 1/2 time
9-16 hrs
Phenergan black box warnings (2)
-Respiratory arrest in children under 2
-Necrosis from infiltration
Phenergan dose
12.5-25 mg IV
Phenergan onset
5 minutes
H2 antagonist main uses (2)
-Decrease gastric acid volume (release)
-Decrease acidity of gastric acid
H2 antagonist side effects (4)
HA/confusion
Diarrhea
Sk-muscle pain
Bradycardia
Downside to prolonged decreased acidity
Overgrowth of bacteria in stomach acid
H2 antagonist drugs (3)
(-tidine)
-Cimetidine (Tagamet)
-Ranitidine (Zantac)
-Famotidine (Pepcid)
Cimetidine trade name
Tagamet
Tagamet metabolism
CYP450
Cleared in urine
Tagamet drug interaction effect
Strongly inhibits CYP450 => inhibits metabolism of other drugs
Tagamet adverse effects (3)
Bradycardia
Hypotension
Impotence
Tagamet dose
150-300 mg IV
1/2 dose in renal impairment
Ranitidine trade name
Zantac
Zantac metabolism
Hepatic metabolism, renal clearance
Zantac effect on hepatic enzymes
No significant interaction
Zantac dose
50 mg diluted 20 cc over 2 min
1/2 dose for renal impairment
Famotidine trade name
Pepcid
Pepcid metabolism
Hepatic metabolism, renal clearance
Pepcid effects on hepatic enzymes
No interference with p450s
Pepcid E 1/2 time
2.5-4 hours
Pepcid potency
Most potency in H2 antagonists
Pepcid dose
20 mg IV
1/2 dose for renal impairment
PPI MOA
Irreversibly bind and inhibit proton pumps
PPI onset
Up to 5 days
PPI Main uses
Controlling gastric acidity and volume
-better for chronic/longer treatment
PPI drug interactions (2)
-Inhibits warfarin metabolism
-Blocks enzyme that activates Plavix
PPI drugs (4)
(-prazole)
-Omeprazole (Prilosec)
-Pantoprazole (protonix)
-Lansoprazole (Prevacid)
-Dexlansoprazole (dexilent)
Omeprazole trade name
Prilosec
Prilosec metabolism
Metabolized by CYPs
Prilosec dose
40 mg in 100cc over 30 min
(Or PO > 3 hrs prior)
Prilosec side effects (6)
HA
agitation
Confusion
Abd pain
N/V
Flatulence
Pantoprazole trade name
Protonix
Protonix metabolism
CYP enzymes
Protonix E 1/2 time (comp)
Longer than prilosec
Protonix dose
40 mg in 100cc over 2-15 min
Particulate antacid based with
Aluminum or magnesium
Non-particulate antacids based with
Sodium, carbonate, citrate, bicarbonate
Antacid MOA
Neutralize acid
Antacid drug
Sodium Citrate (bicitra)
Long term acid neutralization problems (2)
Leads to inhibited breakdown of food
And acid rebound
Long term Magnesium antacid use
Neurologic and neuromuscular impairment
Sodium based antacid considerations
Increased sodium load in hypertensive and cardiac impaired pts
Sodium citrate trade name
Bicitra
Base + acid =
Salt, CO2, and H2O
Bicitra use
Protect against aspiration acid damage, not aspiration
Bicitra onset and duration
Immediate onset
Lose effect 30-60 min
Bicitra dose
15-30 mL PO
