Comparative Pharmacology
Head-to-head clinical analysis: NITRO IV versus NITRO DUR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: NITRO IV versus NITRO DUR.
NITRO IV vs NITRO-DUR
Head-to-head clinical comparison of therapeutic indices and safety profiles.
Nitroglycerin is a vasodilator that primarily acts by relaxing vascular smooth muscle via the release of nitric oxide (NO), which activates guanylate cyclase to increase cGMP, leading to venodilation and, at higher doses, arterial dilation. This reduces preload and afterload, decreasing myocardial oxygen demand.
Nitroglycerin is a prodrug that is converted to nitric oxide (NO) in vascular smooth muscle, activating guanylyl cyclase, increasing cGMP, leading to vasodilation primarily in veins and arteries.
Acute angina pectorisProphylaxis of angina (before exercise or stress)Congestive heart failure (acute)Controlled hypotension during surgeryHypertensive emergencies (off-label)Pulmonary edema (off-label)
Prophylaxis and treatment of angina pectoris due to coronary artery diseaseHeart failure (IV formulation)Hypertensive crisis (IV formulation)Anal fissures (topical ointment)
Initial infusion rate 5 mcg/min via continuous IV infusion, titrate by 5 mcg/min every 3-5 minutes until response; usual maintenance dose 10-20 mcg/min; maximum 200 mcg/min.
Transdermal: Initial 0.2-0.4 mg/h applied once daily, titrate to 0.4-0.8 mg/h; maximum 0.8 mg/h. Remove for 10-12 hours daily to prevent tolerance.
None Documented
None Documented
1-4 minutes (rapidly cleared from blood); terminal half-life ~2-3 minutes due to rapid biotransformation in RBCs and vascular tissue.
2–3 minutes (nitroglycerin); prolonged to ~30 minutes for active metabolites. Clinical context: Requires frequent dosing or continuous administration for sustained effect.
Nitroglycerin is extensively metabolized in the liver by glutathione S-transferases and, to a lesser extent, by arterial walls. It undergoes denitration to form 1,2- and 1,3-glyceryl dinitrate, which have weaker vasodilatory activity.
Metabolized by glutathione S-transferases (GSTs) in the liver and erythrocytes, producing glycerol dinitrate and nitrite ions.
Renal (minimal, <1% unchanged) and hepatic metabolism; metabolites excreted renally.
Primarily renal (>80% as inactive metabolites; <1% unchanged nitroglycerin). Minor biliary/fecal elimination.
60% bound to albumin.
~60% (mainly to albumin).
3-4 L/kg (high, due to extensive tissue uptake, especially vascular smooth muscle).
~3 L/kg (extensive tissue distribution).
IV: 100% (not administered via other routes due to extensive first-pass metabolism).
Transdermal: ~70% (relative to IV). Oral: <10% (extensive first-pass metabolism).
No dose adjustment required for GFR ≥30 mL/min; for GFR <30 mL/min, consider dose reduction due to risk of methemoglobinemia and cyanide toxicity, monitor closely.
No dose adjustment needed for any degree of renal impairment.
Child-Pugh class A: no adjustment; Child-Pugh class B: reduce dose by 50%; Child-Pugh class C: avoid use or use with extreme caution, reduce dose by 75%.
Child-Pugh Class A: No adjustment. Child-Pugh Class B: Use with caution, consider dose reduction by 25-50% due to reduced metabolism. Child-Pugh Class C: Avoid use or use minimal effective dose (e.g., 0.2 mg/h) with close monitoring.
0.25-0.5 mcg/kg/min IV continuous infusion, titrate by 0.5-1 mcg/kg/min every 3-5 minutes; maximum 5 mcg/kg/min for children.
Safety and efficacy not established in pediatric patients; no standard dosing guidelines.
Initiate at lower end of dosing range (5 mcg/min) due to increased sensitivity; titrate slowly with careful hemodynamic monitoring.
Start at low end of dosing range (0.2 mg/h), titrate slowly, monitor for hypotension and dizziness. Increased sensitivity due to age-related vascular changes; may require extended nitrate-free interval (e.g., 12-14 hours).
Nitroglycerin is contraindicated in patients with severe anemia, increased intracranial pressure, or those using phosphodiesterase-5 inhibitors (e.g., sildenafil, tadalafil, vardenafil) due to risk of severe hypotension.
Do not use with phosphodiesterase-5 inhibitors (e.g., sildenafil, tadalafil, vardenafil) due to risk of severe hypotension.
["Hypotension and reflex tachycardia may occur; monitor blood pressure","May exacerbate angina from abrupt discontinuation (tolerance and rebound)","Caution in patients with hypovolemia, right ventricular infarction, or hypertrophic cardiomyopathy","Avoid in patients with constrictive pericarditis or pericardial tamponade","May cause methemoglobinemia, especially with high doses or prolonged use"]
Hypotension, especially in hypovolemic patients; tolerance with chronic use; paradoxical bradycardia and increased angina; exacerbate hypertrophic cardiomyopathy; avoid abrupt discontinuation.
["Allergy to nitroglycerin or nitrates","Severe anemia","Increased intracranial pressure (e.g., head trauma, cerebral hemorrhage)","Concomitant use of phosphodiesterase-5 inhibitors (e.g., sildenafil, tadalafil, vardenafil)","Hypotension (systolic BP < 90 mmHg)","Right ventricular infarction","Constrictive pericarditis","Pericardial tamponade"]
Concomitant use with PDE-5 inhibitors; severe anemia; increased intracranial pressure; hypersensitivity to nitroglycerin; acute circulatory failure; constrictive pericarditis; pericardial tamponade.
Data Pending Review
Data Pending Review
No specific food restrictions. Avoid alcohol as it may enhance vasodilation and hypotension.
Avoid alcohol, as it can enhance hypotensive effects. No specific food restrictions, but high-fat meals may delay absorption of nitroglycerin if administered orally; transdermal route is less affected.
FDA Pregnancy Category C. First trimester: Limited human data; animal studies show fetal harm at high doses. Second/third trimester: Potential risk of fetal bradycardia and hypotension; use only if clearly needed. Avoid near term due to risk of uterine relaxation and hemorrhage.
FDA Pregnancy Category C. First trimester: Animal studies show fetal harm, but no adequate human studies; potential risk cannot be ruled out. Second and third trimesters: Possible fetal bradycardia, hypotension, and reduced placental perfusion; avoid near term due to risk of maternal hypotension and fetal distress.
Unknown excretion in human milk. M/P ratio not established. Short half-life suggests minimal exposure; however, use with caution and consider risk of infant hypotension.
Excreted in breast milk; M/P ratio not established. Use with caution, monitor infant for hypotension or methemoglobinemia; consider pump and discard if high doses used.
No standard dose adjustment in pregnancy. Consider higher initial doses due to increased volume of distribution and clearance, but titrate to effect due to potential for heightened sensitivity.
No specific dose adjustments recommended; however, increased plasma volume may reduce drug concentrations; titrate to effect, avoid hypotension to maintain placental perfusion.
Category C
Category C
Use non-PVC infusion sets to minimize drug adsorption. Monitor for hypotension, especially with concurrent PDE-5 inhibitor use. Tolerance can develop with prolonged infusion; use lowest effective dose. Do not abruptly discontinue after prolonged use to avoid rebound ischemia. Avoid in patients with right ventricular infarction or severe aortic stenosis.
NITRO-DUR (nitroglycerin) transdermal patch is used for angina prophylaxis, not acute attacks. Apply to hairless area, avoid chest if possible to prevent interference with defibrillation. Rotate sites daily to prevent tolerance; remove patch for 10-12 hours daily to maintain nitrate-free interval. Contraindicated with PDE5 inhibitors (sildenafil, tadalafil, vardenafil) due to risk of severe hypotension. Monitor for hypotension, reflex tachycardia, headache.
Report any severe headaches, dizziness, or fainting during infusion.Avoid taking erectile dysfunction medications like sildenafil or tadalafil while on this treatment.Notify your healthcare provider if you have a history of low blood pressure or recent heart attack.The medication will be given by a healthcare professional and vital signs will be monitored closely.Do not stop the infusion suddenly without medical advice.
Apply patch once daily to clean, dry, hairless skin on upper arm, chest, or back.Remove old patch before applying new one.Keep patch on for 12-14 hours then remove for 10-12 hours to prevent tolerance.Do not use during acute angina attack; use sublingual nitroglycerin instead.Avoid alcohol and erectile dysfunction drugs (Viagra, Cialis, Levitra) while using this patch.Common side effects: headache, dizziness, flushing. Report severe headache or fainting.Do not stop abruptly; may cause rebound angina.