Prescription Drug Index

Nitroglycerin is prescribed to prevent and treat angina pectoris (suffocating chest pain). This condition occurs when the coronary arteries become constricted and are not able to carry sufficient oxygen to the heart muscle. Nitroglycerin is thought to improve oxygen flow by relaxing the walls of arteries and veins thus allowing them to dilate.

Nitroglycerin is used in different forms. As a patch or ointment nitroglycerin may be applied to the skin. The patch and the ointment are for prevention of chest pain. Swallowing nitroglycerin in capsule or tablet form also helps to prevent chest pain from occurring.

In the form of sublingual (held under the tongue) or buccal (held in the cheek) tablets or in oral spray (sprayed on or under the tongue) nitroglycerin helps relieve chest pain that has already occurred. The spray can also prevent anginal pain. The type of nitroglycerin you use will depend on your condition.

The following section is intended to provide guidelines for taking nitroglycerin. Follow your doctor’s instructions carefully for using nitroglycerin in the form prescribed for you.

ADULTS

Sublingual or Buccal Tablets

At the first sign of chest pain 1 tablet should be dissolved under the tongue or inside the cheek. You may repeat the dose every 5 minutes until the pain is relieved. If your pain continues after you have taken 3 tablets in a 15-minute period notify your doctor or seek medical attention immediately.

You may take sublingual or buccal nitroglycerin from 5 to 10 minutes before starting activities that may cause chest pain.

Patch Form

A patch is applied to the skin for 12 to 14 hours. After this time the patch is removed; it is not applied again for 10 to 12 hours (a patch-off period). A new patch should then be applied to a new area on the body that is non-hairy and is above the waist but below the neck. Apply the patch as soon as you remove it from its protective pouch.

Spray Form

At the first sign of chest pain spray 1 or 2 pre-measured doses onto or under the tongue 5 minutes apart. You should not use more than 3 doses within a 15-minute period. If your chest pain continues you should contact your doctor or seek medical attention immediately.

The spray can be used 5 to 10 minutes before activity that might precipitate an attack.

Ointment Form

Your initial dose may be a daily total of 1 inch of ointment. Apply one-half inch on rising in the morning and the remaining one-half inch 6 hours later. If needed follow your doctor’s instructions for increasing your dosage. Apply in a thin uniform layer regardless of the amount of your dosage. There should be a daily period where no ointment is applied. Usually the "ointment-off" period will last from 10 to 12 hours.

Absorption varies with site of application--more is absorbed through the chest.

Sustained-Release Capsules or Tablets

The smallest effective amount should be taken 2 or 3 times a day at 8- to 12-hour intervals.

CHILDREN

The safety and effectiveness of nitroglycerin have not been established for children.

OLDER ADULTS

In general dosages less than the above adult dosages are recommended since the elderly may be more susceptible to low blood pressure and headaches.

Note:

The content in this section is provided for informational purposes only. This information regarding the following Canadian drugs is not intended to replace or act as a substitute for information or advice provided by your physician. You should always consult a physician before beginning a new medication. Moreover, prescription drugs should only be obtained with a doctor's prescription.

If you would like more information on different medications, please click here for a list of the most reliable sites on the internet for prescription drug information.