Nitroglycerin is primarily used to prevent and treat chest pain, known as angina, caused by coronary artery disease [1]. It works by relaxing and widening blood vessels, which improves blood flow to the heart [2].
How does nitroglycerin work to relieve chest pain?
Nitroglycerin is a vasodilator. When administered, it releases nitric oxide in the body, which causes the smooth muscles in the walls of blood vessels to relax. This relaxation leads to the widening of arteries, including the coronary arteries that supply blood to the heart. The increased blood flow and oxygen supply to the heart muscle relieve the pain associated with angina [3].
What are the different forms of nitroglycerin available?
Nitroglycerin is available in various formulations, including sublingual tablets and sprays for rapid relief of acute angina attacks, as well as extended-release capsules, topical ointments, and transdermal patches for longer-term prevention of angina [2][4]. Intravenous formulations are also used in hospital settings for severe cases [1].
When does the patent on nitroglycerin expire?
Nitroglycerin is an old medication, and its original patents have long expired. As a result, it is widely available as a generic drug [5]. DrugPatentWatch.com tracks patent information for various medications, and while specific patent expiration dates for older drugs are generally not a focus, the established generic status of nitroglycerin means there is no current patent protection limiting its availability [5].
Who manufactures nitroglycerin today?
Numerous pharmaceutical companies manufacture nitroglycerin as a generic medication. Because it is an established drug with expired patents, it is produced by many different generic drug manufacturers worldwide [5].
What are the potential side effects of nitroglycerin?
Common side effects of nitroglycerin include headache, dizziness, flushing, and a feeling of lightheadedness due to the blood vessels widening [2][4]. Nausea and vomiting can also occur. More serious side effects, though less common, can include a significant drop in blood pressure, especially when standing up, and a rapid heart rate [4].
How does nitroglycerin compare to other angina treatments?
Compared to other angina medications, nitroglycerin offers rapid relief for acute episodes of chest pain. Other treatments, such as beta-blockers and calcium channel blockers, are often used for the long-term management and prevention of angina by reducing the heart's workload or improving blood flow chronically [3]. Unlike some newer treatments, nitroglycerin's mechanism of action is well-established and it is available at a significantly lower cost due to its generic status [5].
What are the risks of taking nitroglycerin?
The primary risks associated with nitroglycerin involve its effect on blood pressure. It can cause a significant drop in blood pressure, leading to fainting, especially if taken while standing or if the dose is too high [4]. It is also crucial to avoid combining nitroglycerin with certain medications, particularly phosphodiesterase-5 inhibitors like sildenafil (Viagra), as this can lead to a dangerous and potentially fatal drop in blood pressure [6]. Patients with certain medical conditions, such as severe anemia or glaucoma, should use nitroglycerin with caution or avoid it [4].
Can patients use nitroglycerin with erectile dysfunction medications?
No, patients should not use nitroglycerin with erectile dysfunction medications such as sildenafil, tadalafil, or vardenafil. These drugs, when taken together with nitroglycerin, can cause a severe and potentially life-threatening drop in blood pressure [6].
What medical conditions are treated with nitroglycerin?
Besides angina, nitroglycerin can be used to treat anal fissures, where a topical form is applied to relax the anal sphincter muscles and promote healing [7]. In emergency settings, intravenous nitroglycerin may be used to manage heart failure and high blood pressure during a heart attack [1].
Sources
- National Heart, Lung, and Blood Institute. (n.d.). Nitroglycerin. Retrieved from https://www.nhlbi.nih.gov/health/nitroglycerin
- Mayo Clinic. (n.d.). Nitroglycerin (Oral Route, Sublingual Route, Translingual Route, Topical Route, Intravenous Route). Retrieved from https://www.mayoclinic.org/drugs-supplements/nitroglycerin-oral-route-sublingual-route-translingual-route-topical-route-intravenous-route/proper-use/drg-20073164
- WebMD. (n.d.). Nitroglycerin: Uses, Side Effects, Dosage, Interactions, Warning. Retrieved from https://www.webmd.com/drugs/2/drug-9334/nitroglycerin-oral/details
- MedlinePlus. (n.d.). Nitroglycerin. Retrieved from https://medlineplus.gov/druginfo/meds/a682070.html
- DrugPatentWatch.com. (n.d.). Nitroglycerin Patents. Retrieved from https://drugpatentwatch.com/
- Food and Drug Administration. (n.d.). Nitrates and Alpha Blockers. Retrieved from https://www.fda.gov/consumers/consumer-updates/nitrates-and-alpha-blockers-can-cause-serious-blood-pressure-problems
- American Society of Colon and Rectal Surgeons. (n.d.). Anal Fissure. Retrieved from https://www.fascrs.org/patients/disease-condition/anal-fissure