SIDE EFFECTS: Headache, dizziness, lightheadedness, nausea, and flushing may occur as your body adjusts to the medication. If any of these effects last or get worse, tell your doctor or pharmacist promptly. Headache is often a sign that this medication is working. Your doctor may recommend treating headaches with an over-the-counter pain reliever (such as acetaminophen). If the headaches continue or become severe, tell your doctor promptly. To reduce the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position. Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. This medication may rarely cause nerve problems. Tell your doctor promptly if you experience numbness or tingling. Your doctor may recommend a vitamin B6 supplement (pyridoxine). Tell your doctor right away if you have any serious side effects, including: severe tiredness, aching/swollen joints, rash on nose and cheeks, swollen glands, signs of kidney problems (such as change in the amount of urine, bloody/pink urine), signs of infection (such as fever, chills, persistent sore throat), easy bruising/bleeding, fainting, fast/irregular/pounding heartbeat. Get medical help right away if you have any very serious side effects, including: chest/jaw/left arm pain. A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

HOW TO USE: Take this medication by mouth, usually 3 times daily or as directed by your doctor. The dosage is based on your medical condition and response to treatment. Your doctor may start you at a low dose and gradually increase your dose. Follow your doctor's instructions carefully. Use this medication regularly to get the most benefit from it. To help you remember, take it at the same times each day. Do not stop taking this medication without consulting your doctor. Some conditions may become worse when the drug is suddenly stopped. Your dose may need to be gradually decreased. Tell your doctor if your condition worsens.

PRECAUTIONS: Before taking this medication, tell your doctor or pharmacist if you are allergic to either isosorbide dinitrate or hydralazine; or to similar drugs (such as isosorbide mononitrate, nitroglycerin); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details. Before using this medication, tell your doctor or pharmacist your medical history, especially of: other heart problems (such as recent heart attack, rheumatic heart disease of the mitral valve), previous stroke, low blood pressure, blood vessel problems, dehydration, recent head injury, anemia, kidney problems. This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis). Before having surgery, tell your doctor or dentist that you are using this medication. Older adults may be more sensitive to the side effects of this drug, especially dizziness and lightheadedness, which could increase the risk of falls. During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor. Hydralazine passes into breast milk. It is unknown if isosorbide dinitrate passes into breast milk. Consult your doctor before breast-feeding.

DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval. Some products that may interact with this drug include: certain drugs to treat migraine headaches (ergot alkaloids such as ergotamine), drugs to treat erectile dysfunction-ED or pulmonary hypertension (such as sildenafil, tadalafil), MAO inhibitors (isocarboxazid, linezolid, metaxalone, methylene blue, moclobemide, phenelzine, procarbazine, rasagiline, safinamide, selegiline, tranylcypromine), riociguat. Some products have ingredients that could worsen your heart failure. Tell your pharmacist what products you are using, and ask how to use them safely (especially cough-and-cold products, diet aids, or NSAIDs such as ibuprofen/naproxen). Isosorbide dinitrate is very similar to isosorbide mononitrate. Do not use medications containing isosorbide mononitrate while using isosorbide dinitrate. This medication may interfere with certain laboratory tests (including blood cholesterol levels), possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this drug.

OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: slow heartbeat, vision changes, severe nausea/vomiting, sweating, cold/clammy skin, bluish fingers/toes/lips, chest/jaw/left arm pain.