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Nitroglycerin Patient Tips

Medically reviewed on Nov 21, 2017 by C. Fookes, BPharm.

How it works

  • Nitroglycerin relaxes smooth muscle contained within the walls of blood vessels (particularly veins) which dilates (widens) them. This helps to relieve chest pain that is caused by a narrowing of the blood vessels, and also reduces how hard the heart has to work to pump blood around the body, reducing blood pressure.
  • Nitroglycerin belongs to a group of medicines called nitrates.

Upsides

  • Nitroglycerin sublingual spray or tablets may be used to relieve symptoms of angina (chest pain) in suitable people.
  • Nitroglycerin injection may be given by a doctor's office or before surgery to treat or lower high blood pressure, to control heart failure associated with a heart attack, or to treat angina in suitable patients.
  • Nitroglycerin rectal ointment may be used to treat anal fissure pain.
  • Available as a buccal tablet, a sublingual spray or tablet, a transdermal ointment or film, a rectal ointment, a sublingual powder, an intravenous solution, and an oral capsule.
  • Generic nitroglycerin is available.

Downsides

If you are between the ages of 18 and 60, take no other medication or have no other medical conditions, side effects you are more likely to experience include:

  • Dizziness, light-headedness, headache, and low blood pressure may occur. This may affect a person's ability to drive or operate machinery. Alcohol, hot weather, and exercise may worsen these effects and result in fainting. Blurred vision may also occur.
  • Rarely, allergic reactions, flushing, severe dizziness or a headache or persistent nausea or vomiting may occur. Seek urgent medical help.
  • Alcohol toxicity has been reported when high-dose nitroglycerin injection has been given in conjunction with alcohol, or when certain medications (such as disulfiram, cephalosporin antibiotics) are taken at the same time as nitroglycerin and alcohol. Do not drink alcohol while using nitroglycerin.
  • Tolerance can develop to nitroglycerin's effect (tolerance is when the same dose no longer produces the same effect). To prevent this from developing, nitroglycerin-free intervals of 10-12 hours between doses are recommended. However, if you are experiencing chest pain, which is unrelieved by one nitroglycerin dose, it is acceptable to have another dose and call for urgent medical help.
  • May not be suitable for some people including the elderly; those with a history of stroke or bleeding in the brain; with anemia, glaucoma, migraines or swelling of the heart sac; on medication for erectile dysfunction; or where blood flow back to the heart is restricted.
  • May interact with a number of other medications including medicines used to treat erectile dysfunction (such as sildenafil and tadalafil), topical anesthetics, antidepressants and antipsychotics, riociguat, diuretics, ergot derivatives, and tizanidine. Alcohol may increase the side effects of nitroglycerin. May affect the results of some medical tests.
  • Nitroglycerin can be toxic to children and pets. Keep well out of reach.

Notes: In general, seniors or children, people with certain medical conditions (such as liver or kidney problems, heart disease, diabetes, seizures) or people who take other medications are more at risk of developing a wider range of side effects. For a complete list of all side effects, click here.

Bottom Line

Nitroglycerin dilates veins, relieving chest pain and lowering blood pressure. It has a very short duration of action and may not be suitable for some people.

Tips

  • If you are taking this medicine to relieve symptoms of angina, keep it on hand at all times. Always refill your prescription before you run out of nitroglycerin.
  • Take nitroglycerin spray or sublingual tablets at the first sign of chest pain. Sit down if you can before taking a dose. Place the sublingual tablet under your tongue and allow it to dissolve slowly. Take exactly as directed by your doctor. Do not use more than three tablets in 15 minutes.
  • Nitroglycerin spray needs to be primed before use or if it has not been used for six weeks. Spray the dose of Nitrolingual preferably onto or under the tongue; do not inhale. Close your mouth after the spray. Avoid rinsing the mouth for five to ten minutes after. Keep the spray canister away from heat or flames because it may explode.
  • Talk to your doctor about taking nitroglycerin five to ten minutes before any activity that typically causes you chest pain.
  • If you develop severe chest pain or symptoms of a heart attack, or if your chest pain lasts more than five minutes, seek emergency medical attention.
  • Always sit or stand up slowly when rising from a lying down or seated position as nitroglycerin may cause a drop in blood pressure.
  • Contact your doctor immediately if you develop a slow heartbeat or new or worsening chest pain after using nitroglycerin.
  • Sometimes nitroglycerin will cause a burning or stinging in your mouth. This is not a sign that the medicine is working. Do not use more nitroglycerin just because you didn't notice the burning or stinging.
  • Tell other health professionals (such as your dentist) that you take nitroglycerin.
  • Do not take medicines for erectile dysfunction (ED), such as Viagra, Cialis or Levitra, while you are taking nitroglycerin as the combination may dangerously drop your blood pressure. Talk to your doctor or pharmacist before taking any other medications with nitroglycerin, because some may not be compatible with nitroglycerin.
  • Do not take nitroglycerin if you have circulation problems, are in shock, have severe anemia, or a feeling of pressure inside your head.

Response and Effectiveness

  • Nitroglycerin acts in the body for an extremely short period of time, although it is metabolized to longer-lived active metabolites. However, these are less effective vasodilators than nitroglycerin.

References

  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use nitroglycerin only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that this information is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This drug information does not endorse drugs, diagnose patients or recommend therapy. It is an informational resource designed as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of this information. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2017 Drugs.com. Revision Date: 2017-11-21 02:05:30

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