Nitroglycerin Uses, Dosage, Side Effects, Food Interaction and all others data.

The principal pharmacological action of nitroglycerin is relaxation of vascular smooth muscle and consequent dilatation of peripheral arteries and veins. Dilatation of the veins promotes peripheral pooling of blood and decreases venous return to the heart, thereby reducing left ventricular end-diastolic pressure and pulmonary capillary wedge pressure (preload). Arteriolar relaxation reduces systemic vascular resistance, systolic arterial pressure, and mean arterial pressure (after load). Dilatation of the coronary arteries also occurs.

Nitroglycerin causes the relaxation of vascular smooth muscles, causing arteriolar and venous dilatation. It reduces cardiac preload and afterload and reduces coronary artery spasm, decreasing systemic vascular resistance as well as systolic and diastolic blood pressure. The reduction of cardiac work by nitroglycerin is thought to cause the most relief of anginal symptoms, with some contributions from arteriolar dilatation effects.

Trade Name Nitroglycerin
Availability Prescription only
Generic Nitroglycerin
Nitroglycerin Other Names Glycerin trinitrate, Glycerol trinitrate, Glyceroli trinitratis, Glyceroltrinitrat, Glyceryl trinitrate, Nitroglicerina, Nitroglycerin, Nitroglycerine, Nitroglycerol, Nitromed, Trinitrine, Trinitroglycerin, Trinitroglycerol
Related Drugs amlodipine, aspirin, lisinopril, metoprolol, losartan, furosemide, carvedilol, hydrochlorothiazide, propranolol, spironolactone
Weight 2.5mg, 6.5mg, 9mg, 400mcg, 0.4mg, 0.3mg, 0.6mg, 0.4%, 2%, 0.1mg/hr, 0.2mg/hr, 0.3mg/hr, 0.4mg/hr, 0.6mg/hr, 0.8mg/hr,
Type Intravenous, Oral Capsule, Extended Release, Sublingual Powder, Sublingual Spray, Sublingual Tablet, Oral/sublingual, Rectal Ointment, Rectal, Transdermal Ointment, Topical, Transdermal Film, Transdermal
Formula C3H5N3O9
Weight Average: 227.0865
Monoisotopic: 227.002578773
Protein binding

After a sublingual dose of nitroglycerin, at concentrations in the plasma ranging from 50 to 500 ng/mL, plasma protein binding of nitroglycerin is about 60%. The plasma protein binding of the metabolites 1,2-dinitroglycerin is 60% and that of 1,3-dinitroglycerin is 30%.

Groups Approved, Investigational
Therapeutic Class Nitrates: Coronary vasodilators
Available Country United States, Switzerland
Last Updated: September 19, 2023 at 7:00 am


Nitroglycerin Tablet is used for the prophylaxis of chronic stable angina pectoris.

Nitroglycerin Spray is used for acute relief of an attack or prophylaxis of angina pectoris due to coronary artery disease.

Nitroglycerin Injection is used for the treatment of peri-operative hypertension; for controlling of congestive heart failure in the setting of acute myocardial infarction; for treatment of angina pectoris in patients who have not responded to sublingual nitroglycerin and beta blockers and for induction of Intraoperative hypotension.

Nitroglycerin is also used to associated treatment for these conditions: Angina Attacks, Angina Pectoris, Chronic Anal Fissures, Congestive Heart Failure (CHF), Coronary Artery Spasm, Gastroesophageal variceal hemorrhage prophylaxis, Perioperative Hypertension, Esophageal spastic disorders

How Nitroglycerin works

Nitroglycerin is converted by mitochondrial aldehyde dehydrogenase (mtALDH) to nitric oxide (NO), an active substance which then activates the enzyme guanylate cyclase. The activation of this enzyme is followed by the synthesis of cyclic guanosine 3',5'-monophosphate (cGMP), activating a cascade of protein kinase-dependent phosphorylation events in smooth muscles. This process eventually leads to the dephosphorylation of the myosin light chain of smooth muscles, causing relaxation and increased blood flow in veins, arteries and cardiac tissue.. The above processes lead to decreased work of the heart decreased blood pressure, relief of anginal symptoms, and increased blood flow to the myocardium.One in vitro study using mouse aorta suggests that nitric oxide (an activated metabolite of nitroglycerin) targets the natriuretic peptide receptors.


Nitroglycerin dosage

Tablet or Capsule-

Adults and Elderly Patients: Dosage should be adjusted to the requirements of the individual patient but will usually be 1 or 2 tablets taken three times daily. The lowest effective dose should be used.


At the onset of an attack, 1 or 2 metered sprays should be administered under the tongue. No more than 3 metered sprays are recommended within a 15-minute period. If the chest pain persists, prompt medical attention is recommended. NitroglycerinSpray may be used prophylactically 5 to 10 minutes prior to engaging in activities which might precipitate an acute attack.

Intravenous Infusion-

Nitroglycerin injection is a concentrated, potent drug which must be diluted in dextrose (5%) injection or sodium chloride (0.9%) injection prior to its infusion. Nitroglycerin injection should not be mixed with other drugs. This is not for direct intravenous injection.

Initial Dilution: Aseptically transfer the contents of one nitroglycerin ampoule (containing 50 mg of nitroglycerin) into a 500 ml glass bottle of either Dextrose (5%) Injection or Sodium Chloride Injection (0.9%). This yields a final concentration of 100mcg/ml.

Maintenance Dilution: It is important to consider the fluid requirements of the patient as well as the expected duration of infusion in selecting the appropriate dilution of Nitroglycerin Injection. After the initial dosage titration, the concentration of the solution may be increased, if necessary, to limit fluids given to the patient. The nitroglycerin concentration should not exceed 400 mcg/ml.

Side Effects

Side-effects include facial flushing, headache, dizziness and postural hypotension which may be associated with reflex tachycardia or paradoxical bradycardia. Toxic effects of Nitroglycerin include vomiting, restlessness, cyanosis, methaemoglobinaemia and syncope.


LD50 information The oral LD50 of nitroglycerin in rats is 105 mg/kg and the LD50 of the intravenous form in rats is 23.2 mg/kg.

Overdose information An overdose of nitroglycerin can lead to a variety of hemodynamic effects. General effects may include vertigo, fever, flushed skin, and diaphoresis. Cardiorespiratory symptoms may include syncope, dyspnea, decreased heart rate, or palpitations. Neurologic manifestations can include paralysis, seizures, coma, and death. There are no known antidotes to an overdose of nitroglycerin, and it is not known whether its metabolites can be removed from the circulation. If hypotension occurs due to an overdose with nitroglycerin, elevate the lower limbs and administer an intravenous infusion of normal saline or other fluids if necessary to maintain central fluid volume.


Only the smallest dose required for effective control of the acute anginal attack should be used. Excessive use may lead to the development of tolerance. This drug should be used with caution in patients who may be volume-depleted or are already hypotensive.


Orthostatic hypotension may occur with the combined use of calcium channel blockers, antihypertensive agents, phenothiazine, and tricyclic antidepressants. Use of alcohol with nitroglycerin may produce severe hypotension and collapse. Oral nitroglycerin may enhance the bioavailability of dihydroergotamine.

Food Interaction

  • Avoid alcohol.

Nitroglycerin Alcohol interaction

[Minor] The ethyl alcohol and propylene glycol vehicle of some intravenous nitroglycerin preparations may cause sedation and hypotension.

Sedation and hypotension also may result when one of these preparations is coadministered with ethanol.

Management consists of monitoring mental status.

Volume of Distribution

The volume of distribution of nitroglycerin is 3 L/kg.

Elimination Route

Nitroglycerin is rapidly absorbed and is often used in emergency situations for this reason. After a sublingual dose of 0.5 mg of nitroglycerin, peak concentration was reached by an average of in 4.4 minutes after administration and was measured to be 2.56 ng/ml.

Cmax following a 0.6mg dose of sublingual nitroglycerin was measured to be 2.1 ng/mL and AUC was 14.9 minutes, and Tmax was 7.2 minutes. Absolute bioavailability after the administration of sublingual nitroglycerin tablets is about 40%. The bioavailability of nitroglycerin depends on factors such as mucosal metabolism and hydration status, which both affect the absorption of sublingual drugs.

Half Life

In a pharmacokinetic study, the plasma half-life of intravenously administered nitroglycerin was 2.8 ± 0.9 minutes. The FDA label for the intravenous form of nitroglycerin indicates a similar plasma half-life of about 3 minutes. A pharmacokinetic study using sublingual nitroglycerin estimated the plasma half-life to be approximately 6 minutes. The elimination half-lives of 1,2- and 1,3-dinitroglycerin (metabolites of nitroglycerin)range between 32-26 minutes.


The FDA label for the intravenous form of nitroglycerin estimates clearance to be 1 L/kg/min. Apparent clearance after a sublingual dose was measured to be 21.9 L/min in a pharmacokinetic study of 22 patients with ischemic heart disease and angina.

Elimination Route

Metabolism is the main route by which nitroglycerin is eliminated from the body.

Pregnancy & Breastfeeding use

Pregnancy Category C. There are no adequate and well-controlled studies in pregnant women. Nitroglycerin should be given to pregnant women only if clearly needed.

Nursing Mothers: It is not known whether nitroglycerin is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when Nitroglycerin spray is administered to a nursing woman.


Hypersensitivity to nitrates. Obstructive hypertrophic cardiomyopathy. Low cardiac output secondary to hypovolemia. Inferior myocardial infarction with right ventricular involvement. Raised intracranial pressure. Mitral valve propalpse. Glaucoma.

Special Warning

Use in neonates: Safety and efficacy for use in infants and children have not been established.

Use in children: Safety and efficacy for use in children has not been established.

Acute Overdose

Symptoms: Hypotension, reflex tachycardia, pallor, sweating, diarrhoea, weak pulse, collapse, syncope, dizziness, headache, asthenia, nausea, vomiting, methaemoglobinaemia. Bradycardia, psychosis and resp depression may occur in severe poisoning.

Management: Increase central fluid volume through passive elevation of patient’s legs. IV infusion of normal saline or similar fluid may also be necessary. Methylene blue infusion may be given in case of methaemoglobinaemia. Administer oxygen if necessary.

Storage Condition

Store between 15-30° C. Protect from light and moisture. Keep away from the reach of children.

Innovators Monograph

You find simplified version here Nitroglycerin


What is Nitroglycerin used for?

Nitroglycerin is a medication used for heart failure, high blood pressure, anal fissures, painful periods, and to treat and prevent chest pain caused by decreased blood flow to the heart (angina) or due to the recreational use of cocaine. Nitroglycerin is used to treat angina symptoms, such as chest pain or pressure, that happens when there is not enough blood flowing to the heart.

How safe is Nitroglycerin?

Nitroglycerin might be harmful if you don't take it correctly. You should not take Nitroglycerin if you have taken the maximum amount of short-acting Nitroglycerin prescribed by your doctor. You know your blood pressure is very low.

How does Nitroglycerin work?

Nitroglycerin works by relaxing the blood vessels so the heart does not need to work as hard and therefore does not need as much oxygen.

What are the common side effects of Nitroglycerin?

Common side effects of Nitroglycerin are Headache, dizziness, lightheadedness, nausea, flushing, and burning/tingling under the tongue may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly. Headache is often a sign that this medication is working.

Is Nitroglycerin safe during pregnancy?

Nitroglycerin should only be given to a pregnant woman if clearly needed. Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

Is Nitroglycerin safe during breastfeeding?

Nitroglycerin should not be used topically on the nipples during breastfeeding. Nitroglycerin have not been studied during breastfeeding. Observe infants for flushing and discomfort after breastfeeding.

Can I drink alcohol with Nitroglycerin?

If you drink alcohol while you are taking Nitroglycerin, it can cause a rapid heartbeat , sudden changes in blood pressure, dizziness, and fainting. Avoid alcohol if you are taking any Nitroglycerin.

Can I drive after taking Nitroglycerin?

Nitroglycerin can cause dizziness during the first few hours after you take it. You shouldn't drive or use machinery until you know how this medication affects you. This drug can also cause other side effects.

When should be taken of Nitroglycerin?

The tablets is usually taken as needed, either 5 to 10 minutes before activities that may cause attacks of angina or at the first sign of an attack.

How often can I take Nitroglycerin?

Adults 1 or 2 packets placed under the tongue at the first sign of an angina attack. 1 packet may be used every 5 minutes as needed, for up to 15 minutes. Do not take more than 3 packets in 15 minutes. Children use and dose must be determined by your doctor.

How long does Nitroglycerin take to work?

Nitroglycerin tablets usually give relief in 1 to 5 minutes.

How long does Nitroglycerin stay in my system?

Nitroglycerin acts in the body for an extremely short period (the half-life is 1 to 4 minutes), although it is metabolized to longer-lived active metabolites.

Is it safe to take Nitroglycerin every day?

Take this medication by mouth, usually 3 to 4 times daily or as directed by your doctor. It is important to take the drug at the same times each day. Do not change the dosing times unless directed by your doctor. The dosage is based on your medical condition and response to treatment.

How long can I take Nitroglycerin?

1 tablet may be used every 5 minutes as needed, for up to 15 minutes. Do not take more than 3 tablets in 15 minutes.

Does Nitroglycerin stop heart attacks?

Nitroglycerin may not stop the heart attack, but it could lessen the damage by thinning the blood and breaking up clots.

Can Nitroglycerin help anxiety?

Taking Nitroglycerin is a self-empowering act. Being in control ameliorates fear and anxiety. When Nitroglycerin is properly and frequently used, it will improve the patient's quality of life.

Who should not take Nitroglycerin?

You should not use Nitroglycerin if you are also using medicine to treat pulmonary arterial hypertension or erectile dysfunction, or if you have severe anemia (a lack of red blood cells), or increased pressure inside your skull.

What happens if I miss a dose?

Use the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not use two doses at one time.

What happens if I overdose of Nitroglycerin?

Seek emergency medical attention. An overdose of nitroglycerin can be fatal. Overdose symptoms may include a severe throbbing headache, confusion, fever, fast or pounding heartbeats, dizziness, vision problems, vomiting, bloody diarrhea, trouble breathing, cold or clammy skin, fainting, and seizures.

What happen If I suddenly stop taking Nitroglycerin?

If you take Nitroglycerin on a regular schedule to prevent angina, do not stop taking it suddenly or you could have a severe attack of angina.
*** Taking medicines without doctor's advice can cause long-term problems.