Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.
Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.
DRUG CLASS AND MECHANISM: Isosorbide dinitrate is in the class of drugs
called nitrates and it used for treating and preventing angina or heart pain.
Other nitrates include nitroglycerin (Nitrostat, Nitroquick, Nitrolingual,
Nitro-Dur and others) and isosorbide mononitrate (Imdur, Ismo, Monoket).
Isosorbide dinitrate is converted in the body to isosorbide mononitrate which is
the active chemical.
Nitrates are vasodilators (dilators of blood vessels).
Blood returning from the body in the veins must be pumped by the heart through
the lungs and into the body's arteries against the high pressure in the
arteries. In order to accomplish this work, the heart's muscle must produce and
use energy ("fuel"), and this requires oxygen. Angina pectoris (angina) or
"heart pain" is due to an inadequate flow of blood (and oxygen) to the muscle of
the heart. Nitrates, including isosorbide dinitrate, correct the imbalance
between the flow of blood and oxygen to the heart and the work that the heart
must do by dilating (expanding) the arteries and veins in the body. Dilation of
the veins reduces the amount of blood that returns to the heart that must be
pumped. Dilation of the arteries lowers the pressure in the arteries against
which the heart must pump. As a consequence of both effects, the heart works
less and requires less blood and oxygen.
STORAGE: Isosorbide dinitrate should be stored at room temperature, 15-30 C
(59-86 F).
PRESCRIBED FOR: Isosorbide dinitrate is used for the treatment and prevention
of angina caused by coronary artery disease. Only sublingual tablets are used
for immediate treatment of angina because the onset of action of oral isosorbide
dinitrate is not fast enough. Isosorbide dinitrate sometimes is used for
treating congestive heart failure.
DOSING: Isosorbide dinitrate tablets can be taken with or without food. The
sublingual tablets should be dissolved under the tongue and should not be
crushed or chewed. Tolerance (reduced effect after several doses) may develop,
so a drug free period of at least 14 hours is recommended. The recommended doses
of isosorbide dinitrate are:
Tablets: 5-40 mg 2 or 3 times daily
Tablets: (sublingual): 2.5-10 mg
Tablets:
(extended-release) and capsules (sustained-release): 40-80 mg once or twice
daily.
DRUG INTERACTIONS:Sildenafil (Viagra), tadalafil (Cialis) and vardenafil
(Levitra) increase the blood pressure lowering effects of isosorbide dinitrate
and may cause excessive blood pressure reduction. Patients taking isosorbide
dinitrate should not receive sildenafil (Viagra), tadalafil (Cialis), or vardenafil
(Levitra). Severe blood
pressure reduction, especially when changing posture, may occur when isosorbide
dinitrate is combined with calcium channel blockers, for example, diltiazem
(Cardizem, Tiazac, etc.) and verapamil (Calan, Verelan, etc.) which also reduce
blood pressure.
PREGNANCY: There are no adequate studies of isosorbide dinitrate in
pregnant
women.
NURSING MOTHERS: It is not known if isosorbide dinitrate is excreted in human
breast-milk.
SIDE EFFECTS:Headaches are the most common side effect and usually are
dose-related (increase with higher doses). Flushing may occur because isosorbide
dinitrate dilates blood vessels. Isosorbide dinitrate may cause a drop in blood
pressure when rising from a sitting position (orthostatic hypotension), causing
dizziness, palpitations, and weakness. To reduce the risk of these side effects,
patients should rise slowly from a sitting position.
Congestive heart failure (CHF) is a condition in which the heart's function as a pump is inadequate to meet the body's needs. A poor blood supply resulting from congestive heart failure may cause the body's organ systems to fail, leading to a weakened heart muscle and fluid accumulation in the lungs and body tissue. There are many diseases that can impair pumping efficiency and symptoms of congestive heart failure including fatigue, diminished exercise capacity, shortness of breath, and swelling. Treatments include lifestyle modifications, medications, heart transplant, and therapy.
Angina is chest pain that is due to an inadequate supply of oxygen to the heart muscle.
Angina can be caused by coronary artery disease or spasm of the coronary
arteries. EKG, exercise treadmill, stress echocardiography, stress thallium, and cardiac
catheterization are important tests used in the diagnosis of angina.
Chest pain is a common complaint by a patient in the ER. Causes of chest pain include broken or bruised ribs, pleurisy, pneumothorax, shingles, pneumonia, pulmonary embolism, angina, heart attack, costochondritis, pericarditis, aorta or aortic dissection, and reflux esophagitis. Diagnosis and treatment of chest pain depends upon the cause and clinical presentation of the patient's chest pain.
Heart disease (coronary artery disease) is caused by a buildup of cholesterol deposits in the coronary arteries. Risk factors for heart disease include smoking, high blood pressure, heredity, diabetes, peripheral artery disease, and obesity. Symptoms include chest pain and shortness of breath. There are a variety of tests used to diagnose coronary artery disease. Treatment includes life-style changes, medications, procedures, or surgery.
Achalasia is a disease of the esophagus that mainly affects young adults. Abnormal function of nerves and muscles of the esophagus causes difficulty swallowing and sometimes chest pain.
Heart failure is caused by many conditions including coronary artery disease, heart attack, cardiomyopathy, and conditions that overwork the heart. Symptoms of heart failure include congested lungs, fluid and water retention, dizziness, fatigue and weakness, and rapid or irregular heartbeats.
Coronary artery disease is the most common cause of death in the United
States. Over a million people each year will have a heart attack and 25% will
die before they get to the hospital while or in the Emergency Department.
Prevention is the key to treatment of heart disease.
Diagnosis of heart disease is often made by careful history taken by a health care
practitioner.
Some individuals may have atypical symptoms, including almost none at all.
The testing strategy to confirm the diagnosis and plan appropriate
treatment needs to be individualized for each patient diagnosed with heart
disease.
Treatment of heart disease depends upon the severity of disease, and is often directed by the
symptoms experienced by the affected individual.
Introduction to heart disease
The heart is like any other muscle, requiring oxygen and nutrient-rich blood for it t...