Nitroglycerin

How it works

     * Nitroglycerin relaxes smooth muscle contained within the walls of
       blood vessels (particularly veins) which dilates (widens) them.
       This helps to relieve chest pain that is caused by a narrowing of
       the blood vessels, and also reduces how hard the heart has to work
       to pump blood around the body, reducing blood pressure.
     * Nitroglycerin belongs to a group of medicines called nitrates.

Upsides

     * Nitroglycerin sublingual spray or tablets may be used to relieve
       symptoms of angina (chest pain) in suitable people.
     * Nitroglycerin injection may be given by a doctor's office or before
       surgery to treat or lower high blood pressure, to control heart
       failure associated with a heart attack, or to treat angina in
       suitable patients.
     * Nitroglycerin rectal ointment may be used to treat anal fissure
       pain.
     * Available as a buccal tablet, a sublingual spray or tablet, a
       transdermal ointment or film, a rectal ointment, a sublingual
       powder, an intravenous solution, and an oral capsule.
     * Generic nitroglycerin is available.

Downsides

   If you are between the ages of 18 and 60, take no other medication or
   have no other medical conditions, side effects you are more likely to
   experience include:
     * Dizziness, light-headedness, headache, and low blood pressure may
       occur. This may affect a person's ability to drive or operate
       machinery. Alcohol, hot weather, and exercise may worsen these
       effects and result in fainting. Blurred vision may also occur.
     * Rarely, allergic reactions, flushing, severe dizziness or a
       headache or persistent nausea or vomiting may occur. Seek urgent
       medical help.
     * Alcohol toxicity has been reported when high-dose nitroglycerin
       injection has been given in conjunction with alcohol, or when
       certain medications (such as disulfiram, cephalosporin antibiotics)
       are taken at the same time as nitroglycerin and alcohol. Do not
       drink alcohol while using nitroglycerin.
     * Tolerance can develop to nitroglycerin's effect (tolerance is when
       the same dose no longer produces the same effect). To prevent this
       from developing, nitroglycerin-free intervals of 10-12 hours
       between doses are recommended. However, if you are experiencing
       chest pain, which is unrelieved by one nitroglycerin dose, it is
       acceptable to have another dose and call for urgent medical help.
     * May not be suitable for some people including the elderly; those
       with a history of stroke or bleeding in the brain; with anemia,
       glaucoma, migraines or swelling of the heart sac; on medication for
       erectile dysfunction; or where blood flow back to the heart is
       restricted.
     * May interact with a number of other medications including medicines
       used to treat erectile dysfunction (such as sildenafil and
       tadalafil), topical anesthetics, antidepressants and
       antipsychotics, riociguat, diuretics, ergot derivatives, and
       tizanidine. Alcohol may increase the side effects of nitroglycerin.
       May affect the results of some medical tests.
     * Nitroglycerin can be toxic to children and pets. Keep well out of
       reach.

   Notes: In general, seniors or children, people with certain medical
   conditions (such as liver or kidney problems, heart disease, diabetes,
   seizures) or people who take other medications are more at risk of
   developing a wider range of side effects. For a complete list of all
   side effects, [84]click here.

Bottom Line

   Nitroglycerin dilates veins, relieving chest pain and lowering blood
   pressure. It has a very short duration of action and may not be
   suitable for some people.

Tips

     * If you are taking this medicine to relieve symptoms of angina, keep
       it on hand at all times. Always refill your prescription before you
       run out of nitroglycerin.
     * Take nitroglycerin spray or sublingual tablets at the first sign of
       chest pain. Sit down if you can before taking a dose. Place the
       sublingual tablet under your tongue and allow it to dissolve
       slowly. Take exactly as directed by your doctor. Do not use more
       than three tablets in 15 minutes.
     * Nitroglycerin spray needs to be primed before use or if it has not
       been used for six weeks. Spray the dose of Nitrolingual preferably
       onto or under the tongue; do not inhale. Close your mouth after the
       spray. Avoid rinsing the mouth for five to ten minutes after. Keep
       the spray canister away from heat or flames because it may explode.
     * Talk to your doctor about taking nitroglycerin five to ten minutes
       before any activity that typically causes you chest pain.
     * If you develop severe chest pain or symptoms of a heart attack, or
       if your chest pain lasts more than five minutes, seek emergency
       medical attention.
     * Always sit or stand up slowly when rising from a lying down or
       seated position as nitroglycerin may cause a drop in blood
       pressure.
     * Contact your doctor immediately if you develop a slow heartbeat or
       new or worsening chest pain after using nitroglycerin.
     * Sometimes nitroglycerin will cause a burning or stinging in your
       mouth. This is not a sign that the medicine is working. Do not use
       more nitroglycerin just because you didn't notice the burning or
       stinging.
     * Tell other health professionals (such as your dentist) that you
       take nitroglycerin.
     * Do not take medicines for erectile dysfunction (ED), such as
       Viagra, Cialis or Levitra, while you are taking nitroglycerin as
       the combination may dangerously drop your blood pressure. Talk to
       your doctor or pharmacist before taking any other medications with
       nitroglycerin, because some may not be compatible with
       nitroglycerin.
     * Do not take nitroglycerin if you have circulation problems, are in
       shock, have severe anemia, or a feeling of pressure inside your
       head.

Response and Effectiveness

     * Nitroglycerin acts in the body for an extremely short period of
       time, although it is metabolized to longer-lived active
       metabolites. However, these are less effective vasodilators than
       nitroglycerin.

References