Nitrates : Isosorbide Mononitrate
Trade names:
Isoral, Cordil, Isotard
Class: coronary vasodilating effect
Pregnancy:
(Category C) Action:
§ The principal pharmacological action of isosorbide dinitrate is
relaxation of vascular smooth muscle and consequent dilatation of peripheral
arteries and veins, especially the latter.
§ Dilatation
of the veins promotes peripheral pooling of blood and decreases venous return
to the heart, thereby reducing left ventricular end- diastolic pressure and
pulmonary capillary wedge pressure (preload).
§ Arteriolar relaxation reduces systemic vascular resistance,
systolic arterial pressure, and mean arterial pressure (afterload).
§ Dilatation of the coronary arteries also occurs
Uses:
• Prophylaxis and treatment of acute angina pectoris.
• Treatment of chronic angina pectoris.
• Testament of hypertension associated with MI or CHF.
• Nitroglycerin ointment for treatment of Raynaud’s disease.
Dose:
Isosorbide
Mononitrate : initially 20 mg 2–3 times daily or 40 mg twice daily (10
mg twice daily in those who have not previously received nitrates); up to 120
mg daily in divided doses if required
Isosorbide Dinitrate By mouth, daily in divided doses, angina
30–120 mg, left ventricular failure
40–160 mg, up to 240 mg if
required
By intravenous infusion, 2–10 mg/hour; higher
doses up to 20 mg/hour may be required Contraindications:
• 
Sensitivity to
nitrates Hypotension.
Sensitivity to
nitrates Hypotension.
• Sever anemia.
•
Hypotension. Head trauma.
• Cerebral hemorrhage.
Side effects:
1. Headache, syncope, dizziness.
2. Postural hypotension, transient flushing, and palpitation.
3. Topical application may
lead to dermatitis.
v Drug interaction: Antihypertensive agents,
Beta-adrenergic blocking agents, and calcium-channel blocking agent (they may
lead to additive hypotension.
Nursing
considerations:
• medications should be taken on an empty stomach.
• Carry sublingual tablets in a glass bottle, tightly capped.
• If
anginal pain is not relieved in 5 minutes by first sublingual tablet, to take
up to 2 more tablets at 5 minutes interval. If pain has not subsided 5 minutes
after the 3rd tablet, client should be taken to the emergency room.
• Take sublingual tablets 5-15 minutes prior to any situation
likely to cause anginal pain such as climbing stairs.
• Take sublingual tablets while sitting to avoid postural
hypotension.
