Imdur ER

This section provides information on the proper use of a number of products that contain isosorbide mononitrate. It may not be specific to Imdur ER. Please read with care.

Take this medicine exactly as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

This form of nitrate is used to reduce the number of angina attacks over a long time. It will not relieve an attack that has already started because it works too slowly. The extended-release form gradually releases medicine to provide its effect for 8 to 10 hours. Check with your doctor if you also need a fast-acting medicine to relieve the pain of an angina attack.

You should take this medicine first thing in the morning and follow the same schedule each day. This medicine works best if you have a "drug-free" period of time every day when you do not take it. Your doctor will schedule your doses during the day to allow for a drug-free time. Follow the schedule of dosing carefully so the medicine will work properly.

Swallow the extended-release tablet whole with a half glass of water. Do not split, crush, or chew it.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For prevention of angina:
  • For oral dosage form (extended-release tablets):
    • Adults—At first, 30 or 60 milligrams (mg) once a day. Take the dose in the morning right after you wake up. Your doctor may increase your dose as needed.
    • Children—Use and dose must be determined by your doctor.
  • For oral dosage form (tablets):
    • Adults—20 milligrams (mg) two times a day. Take the first dose in the morning right after you wake up, and the second dose 7 hours later.
    • Children—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

This medicine may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert. Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall.

Avoid drinking alcohol. Alcohol may increase certain side effects of isosorbide mononitrate (dizziness, drowsiness, feeling light-headed, or fainting).

Get emergency medical help if you have signs of an allergic reaction to isosorbide mononitrate: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

• a light-headed feeling, like you might pass out;

• worsening angina pain;

• fast or slow heart rate; or

• pounding heartbeats or fluttering in your chest.

Isosorbide mononitrate can cause severe headaches. These headaches may gradually become less severe as you continue to use nitroglycerin. Do not stop taking this medicine to avoid headaches. Ask your doctor before using any headache pain medication.

Common isosorbide mononitrate side effects may include:

• headache; or

• flushing (warmth, redness, or tingly feeling).

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Applies to isosorbide mononitrate: oral tablet, oral tablet extended release

General

The most common adverse effects are headache and dizziness.[Ref]

Nervous system

Very common (10% or more): Headache (up to 57%), dizziness (up to 11%)
Common (1% to 10%): Light-headedness
Frequency not reported: Bitter taste, paresthesia, impaired concentration, tremor, hypoesthesia, migraine, neuritis, paresis, somnolence, fainting, drowsiness
Postmarketing reports: Syncope[Ref]

Cardiovascular

Common (1% to 10%): Cardiovascular disorder, flushing, hypotension
Frequency not reported: Acute myocardial infarction, apoplexy, arrhythmias, bradycardia, edema, hypertension, pallor, palpitations, tachycardia, hot flushes, cardiac failure, arrhythmia, arrhythmia atrial, atrial fibrillation, bundle branch block, extrasystole, ventricular tachycardia, angina pectoris aggravated, heart murmur, heart sound abnormal, myocardial infarction, Q wave abnormality, intermittent claudication, varicose vein, reflex tachycardia, collapse, bradyarrhythmia, paroxysmal bradycardia, orthostatic hypotension[Ref]

Gastrointestinal

Common (1% to 10%): Nausea, abdominal pain, diarrhea, gastrointestinal disturbances
Frequency not reported: Dry mouth, dyspepsia, vomiting, constipation, flatulence, gastric ulcer, gastritis, glossitis, hemorrhagic gastric ulcer, hemorrhoids, loose stools, melena, heartburn[Ref]

Hypersensitivity

Common (1% to 10%): Allergic reaction[Ref]

Hematologic

Frequency not reported: Methemoglobinemia, thrombocytopenia, hypochromic anemia[Ref]

Other

Common (1% to 10%): Fatigue, pain, chest pain, tiredness
Frequency not reported: Susurrus aurium, vertigo, asthenia, fever, flu-like symptoms, malaise, rigors, earache, tinnitus, tympanic membrane perforation, breast pain, feeling of weakness[Ref]

Respiratory

Common (1% to 10%): Upper respiratory infection, increased cough
Frequency not reported: Asthma, dyspnea, sinusitis, bronchitis, bronchospasm, coughing, increased sputum, nasal congestion, pharyngitis, pneumonia, pulmonary infiltration, rales, rhinitis, hypoxia[Ref]

Dermatologic

Common (1% to 10%): Rash, pruritus
Frequency not reported: Sweating, purpura, acne, hair texture abnormal, increased sweating, skin nodule, leg ulcer, exfoliative dermatitis, excessive perspiration, allergic dermatitis, hyperhidrosis[Ref]

Psychiatric

Common (1% to 10%): Emotional lability, sleep disturbances
Frequency not reported: Anxiety, depression, insomnia, nervousness, nightmares, restlessness, confusion, decreased libido, paroniria[Ref]

Musculoskeletal

Very rare (less than 0.01%): Myalgia
Frequency not reported: Back pain, muscle cramps, neck pain, arthralgia, frozen shoulder, muscle weakness, musculoskeletal pain, myositis, tendon disorder, torticollis[Ref]

Metabolic

Frequency not reported: Anorexia, thirst, decreased weight, hyperuricemia, hypokalemia, poor appetite[Ref]

Genitourinary

Frequency not reported: Prostatic disorder, impotence, atrophic vaginitis, polyuria, urinary tract infection[Ref]

Ocular

Frequency not reported: Amblyopia, ptosis, conjunctivitis, photophobia, vision abnormal[Ref]

Immunologic

Frequency not reported: Bacterial infection, moniliasis, viral infection[Ref]

Hepatic

Frequency not reported: Serum glutamic oxaloacetic transaminase (SGOT) increased, serum glutamate-pyruvate transaminase (SGPT) increased[Ref]

Endocrine

Frequency not reported: Pituitary hemorrhage[Ref]

Renal

Frequency not reported: Renal calculus[Ref]

Some side effects of isosorbide mononitrate may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

No adjustment recommended

Safety and efficacy have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

No adjustment recommended