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Nitrate (Buccal mucosa route, chew route, sublingual route)

Brand Names:

  • Nitrolingual
  • NitroMist
  • Nitroquick
  • Nitrostat
  • Nitrotab
  • Apo-Isdn
  • Gen-Nitro
  • Isordil
  • Nitrolingual Pumpspray

Dosage Forms:

  • Tablet
  • Tablet, Extended Release
  • Spray
  • Patch, Extended Release

Uses of This Medicine:

Nitrates are used to treat the symptoms of angina (chest pain). Depending on the type of dosage form and how it is taken, nitrates are used to treat angina in three ways:

  • To relieve an attack that is occurring by using the medicine when the attack begins;
  • To prevent attacks from occurring by using the medicine just before an attack is expected to occur; or
  • To reduce the number of attacks that occur by using the medicine regularly on a long-term basis.

Nitrates are available in different forms. Sublingual nitrates are generally placed under the tongue where they dissolve and are absorbed through the lining of the mouth. Some can also be used buccally, being placed under the lip or in the cheek. The chewable dosage forms, after being chewed and held in the mouth before swallowing, are absorbed in the same way. It is important to remember that each dosage form is different and that the specific directions for each type must be followed if the medicine is to work properly.

Nitrates that are used to relieve the pain of an angina attack include:

  • Sublingual nitroglycerin
  • Buccal nitroglycerin
  • Sublingual isosorbide dinitrate
  • Chewable isosorbide dinitrate

Those that can be used to prevent expected attacks of angina include:

  • Sublingual nitroglycerin
  • Buccal nitroglycerin
  • Sublingual isosorbide dinitrate
  • Chewable isosorbide dinitrate

Products that are used regularly on a long-term basis to reduce the number of attacks that occur include:

  • Buccal nitroglycerin
  • Chewable isosorbide dinitrate
  • Sublingual isosorbide dinitrate

Nitrates work by relaxing blood vessels and increasing the supply of blood and oxygen to the heart while reducing its work load.

Nitrates may also be used for other conditions as determined by your doctor.

These medicines are available only with your doctor's prescription.

Before Using This Medicine:


Tell your doctor if you have ever had any unusual or allergic reaction to medicines in this group or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.


Studies on these medicines have been done only in adult patients, and there is no specific information comparing use of nitrates in children with use in other age groups.

Older adults

Dizziness or lightheadedness may be more likely to occur in the elderly, who may be more sensitive to the effects of nitrates.


Nitrates have not been studied in pregnant women. However, studies in rabbits given large doses of isosorbide dinitrate have shown adverse effects on the fetus. Before taking these medicines, make sure your doctor knows if you are pregnant or if you may become pregnant.


It is not known whether these medicines pass into breast milk. Although most medicines pass into breast milk in small amounts, many of them may be used safely while breast-feeding. Mothers who are taking these medicines and who wish to breast-feed should discuss this with their doctor.

Other medicines

Using medicines in this class with any of the following medicines is not recommended. Your doctor may decide not to treat you with a medication in this class or change some of the other medicines you take.

  • Sildenafil
  • Tadalafil
  • Vardenafil

Using medicines in this class with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Alteplase, Recombinant

Other interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Other medical problems

The presence of other medical problems may affect the use of medicines in this class. Make sure you tell your doctor if you have any other medical problems, especially:

  • Anemia (severe)
  • Glaucoma May be worsened by nitrates
  • Head injury (recent) or
  • Stroke (recent) Nitrates may increase pressure in the brain, which can make problems worse.
  • Heart attack (recent) Nitrates may lower blood pressure, which can aggravate problems associated with heart attack.
  • Kidney disease or
  • Liver disease Effects may be increased because of slower removal of nitroglycerin from the body.
  • Overactive thyroid

Proper Use of This Medicine:

Take this medicine exactly as directed by your doctor. It will work only if taken correctly.

To select a Sublingual tablets for use, pour several into the bottle cap, take one, and pour the others back into the bottle. Try not to hold them in the palm of your hand because they may pick up moisture and crumble.

Sublingual tablets should not be chewed, crushed, or swallowed. They work much faster when absorbed through the lining of the mouth. Place the tablet under the tongue, between the lip and gum, or between the cheek and gum and let it dissolve there. Do not eat, drink, smoke, or use chewing tobacco while a tablet is dissolving.

Buccal extended-release tablets should not be chewed, crushed, or swallowed. They are designed to release a dose of nitroglycerin over a period of hours, not all at once.

  • Allow the tablet to dissolve slowly in place between the upper lip and gum (above the front teeth), or between the cheek and upper gum. If food or drink is to be taken during the 3 to 5 hours when the tablet is dissolving, place the tablet between the upper lip and gum, above the front teeth. If you have dentures, you may place the tablet anywhere between the cheek and gum.
  • Touching the tablet with your tongue or drinking hot liquids may cause the tablet to dissolve faster.
  • Do not go to sleep while a tablet is dissolving because it could slip down your throat and cause choking.
  • If you accidentally swallow the tablet, replace it with another one.
  • Do not use chewing tobacco while a tablet is in place.
  • Chewable tablets must be chewed well and held in the mouth for about 2 minutes before you swallow them. This will allow the medicine to be absorbed through the lining of the mouth.

For patients using nitroglycerin or isosorbide dinitrate to relieve the pain of an angina attack:

  • When you begin to feel an attack of angina starting (chest pains or a tightness or squeezing in the chest), sit down. Then place a tablet in your mouth, either sublingually or buccally, or chew a chewable tablet. This medicine works best when you are standing or sitting. However, since you may become dizzy, lightheaded, or faint soon after using a tablet, it is safer to sit rather than stand while the medicine is working. If you become dizzy or faint while sitting, take several deep breaths and bend forward with your head between your knees.
  • Remain calm and you should feel better in a few minutes.
  • This medicine usually gives relief in 1 to 5 minutes. However, if the pain is not relieved, and you are using:
    • Sublingual tablets, either sublingually or buccally: Use a second tablet. If the pain continues for another 5 minutes, a third tablet may be used. If you still have the chest pains after a total of 3 tablets in a 15-minute period, contact your doctor or go to a hospital emergency room immediately.
    • Buccal extended-release tablets: Use a sublingual (under the tongue) nitroglycerin tablet and check with your doctor. Do not use another buccal tablet since the effects of a buccal tablet last for several hours.

For patients using nitroglycerin or isosorbide dinitrate to prevent an expected angina attack:

  • You may prevent anginal chest pains for up to 1 hour (6 hours for the extended-release nitroglycerin tablet) by using a buccal or sublingual tablet or chewing a chewable tablet 5 to 10 minutes before expected emotional stress or physical exertion that in the past seemed to bring on an attack.

For patients using isosorbide dinitrate or extended-release buccal nitroglycerin regularly on a long-term basis to reduce the number of angina attacks that occur:

  • Chewable or sublingual isosorbide dinitrate and buccal extended-release nitroglycerin tablets can be used either to prevent angina attacks or to help relieve an attack that has already started.


The dose medicines in this class will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of these medicines. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For angina (chest pain):
    • For chewable dosage form (tablets):
      • Adults 5 mg every two to three hours, chewed well and held in mouth for one or two minutes.
      • Children Dose must be determined by your doctor.
    • For sublingual dosage form (tablets):
      • Adults 2.5 to 5 mg every two to three hours.
      • Children Dose must be determined by your doctor.
  • For angina (chest pain):
    • For buccal dosage form (extended-release tablets):
      • Adults 1 mg every five hours while awake. Your doctor may increase your dose.
      • Children Dose must be determined by your doctor.
    • For sublingual dosage form (tablets):
      • Adults 300 to 600 micrograms (mcg) (0.3 to 0.6 mg) every five minutes. If you still have chest pain after a total of three tablets in fifteen minutes, call your doctor or go to the emergency room right away.
      • Children Dose must be determined by your doctor.

Missed dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.


Keep out of the reach of children.

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Do not keep outdated medicine or medicine no longer needed.

For sublingual nitroglycerin

  • Sublingual nitroglycerin tablets may lose some of their strength if they are exposed to air, heat, or moisture for long periods of time. However, if you screw the cap on tightly after each use and you properly store the bottle, the tablets should retain their strength until the expiration date on the bottle.
  • Keep the medicine in the original glass, screw-cap bottle. For patients who wish to carry a small number of tablets with them for emergency use, a specially designed container is available. However, only containers specifically labeled as suitable for use with nitroglycerin sublingual tablets should be used.
  • Do not keep other medicines in the same bottle with the nitroglycerin since they will weaken the nitroglycerin effect.
  • Keep the medicine handy at all times but try not to carry the bottle close to the body. Medicine may lose strength because of body warmth. Instead, carry the tightly closed bottle in your purse or the pocket of a jacket or other loose-fitting clothing whenever possible.

Precautions While Using This Medicine:

Do not take sildenafil (e.g., Viagra), tadalafil (e.g., Cialis), or vardenafil (e.g., Levitra) if you are taking this medicine. When sildenafil, tadalafil, or vardenafil are taken with nitrates, the combination can lower blood pressure and cause dizziness, lightheadedness, or fainting. In some cases, sildenafil, tadalafil, or vardenafil taken with nitrates has caused death.

If you have been taking this medicine regularly for several weeks, do not suddenly stop using it. If you are taking sildenafil, tadalafil, or vardenafil and you experience an angina attack, you must go to the hospital right away. Stopping suddenly may bring on attacks of angina. Check with your doctor for the best way to reduce gradually the amount you are taking before stopping completely.

Dizziness, lightheadedness, or faintness may occur, especially when you get up quickly from a lying or sitting position. Getting up slowly may help. If you feel dizzy, sit or lie down.

The dizziness, lightheadedness, or fainting is also more likely to occur if you drink alcohol, stand for long periods of time, exercise, or if the weather is hot. While you are taking this medicine, be careful to limit the amount of alcohol you drink. Also, use extra care during exercise or hot weather or if you must stand for long periods of time.

After taking a dose of this medicine you may get a headache that lasts for a short time. This is a common side effect, which should become less noticeable after you have taken the medicine for a while. If this effect continues or if the headaches are severe, check with your doctor.

Side Effects of This Medicine:

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

Blurred vision
dryness of mouth
headache (severe or prolonged)
skin rash
Signs and symptoms of overdose (in the order in which they may occur)
Bluish-colored lips, fingernails, or palms of hands
dizziness (extreme) or fainting
feeling of extreme pressure in head
shortness of breath
unusual tiredness or weakness
weak and fast heartbeat
convulsions (seizures)

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common
Dizziness or lightheadedness, especially when getting up from a lying or sitting position
fast pulse
flushing of face and neck
nausea or vomiting

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Last Updated: 6/12/2013
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