What is nitroglycerin?
Nitroglycerin is a vasodilator, a medicine that opens blood vessels
to improve blood flow. It is used to treat
angina—a type of chest pain—that happens when there is
not enough blood flowing to the heart. To improve blood flow to the heart,
nitroglycerin opens up (dilates) the arteries in the heart (coronary arteries), which improves symptoms and
reduces how hard the heart has to work.
Nitroglycerin comes in a quick-acting tablet or spray form or as a
long-acting pill. The quick-acting pill or spray forms are used under the
tongue (sublingually). Your health professional will prescribe the right amount
for you. Do not use another person's nitroglycerin.
When do I use nitroglycerin under the tongue?
Your health professional will advise you when to use your
nitroglycerin. Generally, nitroglycerin under the tongue is used:
- To relieve sudden angina.
- Before
stressful activities that can cause angina, such as walking uphill or having
sexual intercourse.
How do I use nitroglycerin under the tongue?
- Sit or lie down to take your nitroglycerin. If
you are driving, pull over and park the car. Taking nitroglycerin can lower
your blood pressure, which could cause you to pass out if you are standing up.
- For sudden episodes of angina, use nitroglycerin in a tablet or
liquid spray form.
- The tablet should be placed under your
tongue and left until it dissolves. If you accidentally swallow the tablet,
take another. The medicine won't work if it is swallowed.
- To use
the spray, lift your tongue and depress the spray canister button once.
- Take 1 tablet or spray dose. If after 5 minutes
the chest pain is not better or gets worse, call911or other emergency
services immediately.
- After calling
911, continue to stay on the phone with
the emergency operator—he or she will give you further instructions.
- Regardless of what happens, you should let your
health professional know that you had an episode of angina. If this is unusual
for you or if your angina episodes are occurring more frequently or lasting
longer or you need more medicine to control them, tell your health
professional. Report any change in your chest pain (unstable angina) to your health professional.
A fresh tablet should taste bitter and sting when you put it under
your tongue. If it does not, it probably is not effective and you should take
another.
Are there side effects or interactions with other drugs that I should be aware of?
Normal, temporary side effects of nitroglycerin include a warm or
flushed feeling, headache, dizziness, or lightheadedness. You may also feel a
burning sensation under your tongue.
Do not take the erection-enhancing medicines sildenafil (Viagra),
vardenafil (Levitra), or tadalafil (Cialis) if you are taking nitroglycerin.
Combining nitroglycerin with any of these medicines can cause a
life-threatening drop in blood pressure. If you develop chest pain and have
taken one of these erection-enhancing medicines, be sure to tell your health
professional so that you are not given nitroglycerin or another nitrate
medicine.
Do not take the
pulmonary hypertension medicine sildenafil (Revatio)
if you are taking nitroglycerin or another nitrate medicine.
How should I store nitroglycerin?
Store nitroglycerin pills in a dark-colored (such as brown),
airtight, glass container that you cannot see through. Keep nitroglycerin pills
and liquid spray away from heat and moisture.
Can nitroglycerin get old and lose potency?
If nitroglycerin is old, the tablets may not work well. Get a new
prescription as soon as possible if your supply is past the expiration date.
Usually you should replace your tablets every 3 to 6 months. A nitroglycerin
spray may last up to 2 years before it expires.
There are ways to tell whether your nitroglycerin is still
effective. You should have a headache when you use it. Or if you use
nitroglycerin under your tongue, you should feel a slight tingle or burn when
you place it there. If you do not notice these signs, your nitroglycerin is
probably old. In this case, contact your health professional to get a new
prescription. Fill the prescription as soon as possible, and discard your
out-of-date nitroglycerin.