Nitroglycerin (Nitrostat) Flashcards
Drug Classification
Vasodilator/Nitrate
Mechanism of Action
Nitroglycerin is a pro-drug, which must be de-nitrated to form the active metabolite nitric oxide (NO). Then, NO activates the conversion of GTP ->cGMP+2Pi in VSMC. cGMP activates a cascade of reactions that cause a reduction in intracellular Ca2+ ->VSMC relaxation (in arterioles) and decreased cardiac preload and after load.
Pharmacokinetics
- Onset of Action
- Peak Effects
- Duration of Effects
- Half Life
- Onset of Action- 1-2minutes IV, 1-3minutes SL, 30 minutes topical
- Peak Effects- 5-10minutes SL, varies topical
- Duration of Effects- 20-30minutes SL, 3-6hours topical
- Half Life- 1-4 minutes
Indications/Field Use
- Chest Pain associated with angina or MI
- Acute Pulmonary Edema/CHF
Contraindications
- Shock/Hypotension
- Increased ICP
- Children under 12
- ED drugs within 48 hours
Side Effects/Adverse Reactions
HA, dizziness, tachycardia, hypotension, rash, dry mouth, N&V
Dose
Adult:
Spray- 0.4mg SL q3-5 minutes until effect achieved or b/p drops (max 3x25min)
Paste- 1/2-1 inch topical
Tablet- 0.4mg SL q3-5 minutes until effect achieved or b/p drop (max 3x25min)
Precautions
- Expect HA from cerebral vasodilation
- Routine use may cause tolerance
- 12 lead ECG prior to administration - use extreme caution if R side MI
Drug-Drug interactions
Orthostatic(dizzy when standing) hypotension with B blockers, severe hypotension with alcohol