Nitroglycerin
Patients using nitroglycerin regularly may have developed tolerance and require higher doses, alternatively nitroprusside to achieve desirable blood pressure lowring effect.
Drug | Nitroglycerin |
Brand names | Gonitro ®, Minitran ®, Mylan-nitro ®, Nitro-bid ®, Nitro-dur ®, Nitroject ®, Nitrolingual ®, Nitromist ®, Nitrostat ®, Rectiv ®, Trinipatch ® |
Indications | Pulmonary edema, congestive heart failure. Angina pectoris. Hypertension, hypertensive crisis/emergency. Pulmonary hypertension. Blood pressure control. |
Mechanism of action | Nitroglycerin provides nitric oxide (NO) that induces vasodilatation (of both arterioles and veins) via generation of cyclic GMP, which then activates calcium-sensitive potassium channels in the cell membrane. Nitroglycerin is similar in action and pharmacokinetics to nitroprusside, although the latter is more potent. |
Effects | Antihypertensive. Antianginal. |
Time to onset of action | 2 to 5 minutes |
Duration of action | 5 to 10 minutes |
Delivery | IV |
Dose | Initial infusion dose: 5 μg/min. Increase by 5-10 μg/min every 5 min to desired blood pressure. Maximum dose: 100 μg/min. Time to onset of action: 2 to 5 minutes Duration of action: 5 to 10 minutes. |
Adverse effects | Headache (cerebral vasodilation). Tachycardia (due to reflex sympathetic activation). Nausea. Vomiting. Flushing. Palpitations. Tolerance with prolonged use. Methemoglobinemia. Hypoxemia. |
Caution | Proceed with caution in afterload-dependent conditions. |