(LifeWire) - Nitroglycerin was first used in the 19th century as an ingredient in explosives. It subsequently blasted its way into the medical arena as a remedy for angina, the chest pain that results from narrowed cardiac blood vessels. That remains its best-known therapeutic usee.
Nitroglycerin -- which in its medicinal form is not explosive -- works in a similar fashion whether prescribed for heart failure or angina. It dilates the blood vessels around the heart and allows oxygen-rich blood to flow more freely -- both to the heart and to the rest of the body. It also lessens the heart's workload and lowers its need for oxygen. Its rapid action helps patients experiencing angina symptoms -- which may or may not signal an imminent heart attack -- by countering pain and weakness.
Nitroglycerin can be taken in several ways, including ingested in pill form, absorbed through a skin patch or dissolved sublingually (under the tongue). Patients being treated for heart failure in clinical settings often receive nitroglycerin intravenously (through an IV catheter).
The key to the drug's action lies not only in the form it's taken but also the dosage. In 2007, for example, researchers found that critically ill heart failure patients who were given a series of high doses of nitroglycerin suffered fewer complications -- were less likely, for example, to require a breathing tube or ventilator -- than patients who didn't receive the drug.
However, like many other heart failure remedies, nitroglycerin can have significant side effects. Because it can sharply lower blood pressure, it may produce dizziness, nausea or headaches. Among its serious side effects -- which require prompt medical attention -- are ankle swelling, joint or chest pain, fever, abnormal bleeding or bruising and skin rash.
Nitroglycerin can also have harmful interactions with other drugs. In particular, never combine this medication with an erectile dysfunction drug, such as Viagra: The result could be lethal.
"Coronary Artery Disease." umm.edu. 12 Apr. 2006. University of Maryland Medical Center. 19 Nov. 2008 <http://www.umm.edu/patiented/articles/what_other_drugs_used_angi>.
Levy, Phillip, Scott Compton, Robert Welch, George Delgado, Allison Jennett, Neelima Penugonda, Robert Dunne, and Robert Zalenski. "Treatment of Severe Decompensated Heart Failure with High-Dose Intravenous Nitroglycerin." Annals of Emergency Medicine 50:2 (2007) 144-52. 19 Nov. 2008 <http://cat.inist.fr/?aModele=afficheN&cpsidt=18950664>.
"Medications Commonly Used to Treat Heart Failure." americanheart.org. 2008. American Heart Association. 18 Nov. 2008 <http://www.americanheart.org/presenter.jhtml?identifier=118>.
"Nitrates." texasheart.org. Texas Heart Institute at St. Luke's Episcopal Hospital. 18 Nov. 2008 <http://www.texasheart.org/HIC/Topics/Meds/nitrmeds.cfm>.
"Nitroglycerin." umm.edu. 2008. University of Maryland Medical Center. 19 Nov. 2008 <http://www.umm.edu/altmed/drugs/nitroglycerin-092500.htm>.