Isosorbide Mononitrate (Imdur, ISMO, Monoket)

Category:

Cardiac

Description:

Antianginal agent

Indications:

Prevention of angina pectoris
Hypertension (acute) (non-FDA approved)

Contraindications:

Hypersensitivity to nitrates, severe anemia, close-angle glaucoma, postural hypotension
Head trauma

Precautions:

Pregnancy category C; use caution in nursing mothers
Acute MI, hypertrophic cardiomyopathy, glaucoma
Volume depletion, hypotension, abrupt withdrawal
Continuous delivery without nitrate-free interval (tolerance develops)

Adverse Reactions (Side Effects):

CNS: agitation, anxiety, apprehension, confusion, dizziness, dyscoordination, headache, hypoesthesia, hypokinesia, insomnia, nervousness, nightmares, restlessness, vertigo, weakness
CV: atrial fibrillation, cardiovascular collapse, crescendo angina, dysrhythmias, edema, hypotension, PVC’s, rebound hypertension, retrosternal discomfort, syncope, tachycardia
EENT: blurred vision, diplopia
GI: abdominal pain, diarrhea, dyspepsia, involuntary passing of feces, nausea, tenesmus, vomiting
GU: dysuria, impotence, involuntary passing of urine, urinary frequency
HEME: hemolytic anemia, methemoglobinemia
MS: arthralgia, muscle twitching
SKIN: cold sweat, crusty skin lesions, exfoliative dermatitis, flushing, pallor, perspiration, pruritis, rash

Dosage:

Administered orally: Asymmetric dosing regimens provide a daily nitrate-free interval to minimize the development of tolerance.

Adult:
- PO 5-20mg 2 times daily (with the 2 doses 7 hours apart);
- PO SUS REL 30-60mg 1 time daily initially, titrate to 120-240mg 1 time daily if necessary

Special considerations:

Headache may be a marker for drug activity; do not try to avoid by altering treatment schedule; aspirin or acetaminophen may be used for relief
Dissolve SL tablets under tongue; do not crush, chew, or swallow
Do not crush chewable tablets before administering
Avoid alcohol
Make changes in position slowly to prevent fainting

Source: Operational Medicine 2001, Health Care in Military Settings, NAVMED P-5139, May 1, 2001, Bureau of Medicine and Surgery, Department of the Navy, 2300 E Street NW, Washington, D.C., 20372-5300