Nitroglycerin (NTG)

Question 1

Nitroglycerin (NTG): Classification

Answer 1

1. Antianginal

2. Nitrate

Question 2

Nitroglycerin (NTG): Pharmacodynamic

Answer 2

1. Relaxes vascular smooth muscle
2. Nitric oxide in vascular endothelial cells causes formation of cyclic guanosine monophosphate (c-GMP) which inactivates myosin light-chain kinase or stimulates dephosphorelation of myosin phosphate
3. Causes decreased preload and decreased MVO2 (myocardial oxygen consumption)

Question 3

Nitroglycerin (NTG): Pharmacokinetics

Answer 3

1. Sublingual
   - Onset: 1-3 minutes
   - Peak: Unknown
   - Half-life: 1-4 minutes
   - Duration: 30 minutes

Question 4

Nitroglycerin (NTG): Indications

Answer 4

1. Chest discomfort of suspected cardiac ischemic origin

2. Cardiogenic acute pulmonary edema

Question 5

Nitroglycerin (NTG): Contraindications

Answer 5

1. Allergy or known hypersensitivity to NTG or other nitrates
2. Viagra or Levitra in last 24 hours
3. Cialis in last 48 hours
4. Hypotension or uncorrected hypovolemia
5. Severe anemia
6. Constrictive pericarditis and pericardial tamponade
7. Inferior MI on 12 lead ECG

Question 6

Nitroglycerin (NTG): Relative Contraindications

Answer 6

1. Open or closed angle glaucoma

Question 7

Nitroglycerin (NTG): Precautions

Answer 7

1. Use with caution in presence of hepatic or renal insufficiency
2. Patients on concurrent anti-hypertensive therapy

Question 8

Nitroglycerin (NTG): Adverse Effects

Answer 8

1. Hypotension - do not administer if blood pressure is <90 systolic or patient exhibits signs of significant hypoperfusion headache, N/V

Question 9

Nitroglycerin (NTG): Drug to Drug interaction

Answer 9

1. Alcohol and nitroglycerin may have additive vasodilator effects that may lead to hypotension

Question 10

Nitroglycerin (NTG): Dosage

Answer 10

1. 0.4 mg spray SL - repeat q 3 min - maintaining B/P > 90 systolic
2. Infusion: 10 - 200 ug/min (in hospital)