Pharm
Nitroglycerin
search
Nitroglycerin
, Antianginal
History
Albert Nobel stabilized Nitroglycerin for dynamite
Some postulate that he died of Nitroglycerin toxicity
Preparations
Short Acting Nitroglycerin
Long Acting Nitroglycerin
Intravenous Nitroglycerin
Indications
Angina Pectoris
Acute
Myocardial Infarction
Left Ventricular Failure
(
Congestive Heart Failure
)
Contraindications
Aortic Stenosis
Pulmonary Hypertension
Hypotension
Phosphodiesterase Inhibitor
(e.g.
Viagra
)
Right sided
Myocardial Infarction
(seen with inferior
Myocardial Infarction
)
Mechanism
Relaxes vascular smooth muscle
Venous Dilation (more than
Nitroprusside
)
Inhibits venous return (
Preload
)
Decreases intra-myocardial wall tension
Decreases intraventricular work
Reduces left ventricular filling pressure
Decreases myocardial oxygen demand
Reduces
Myocardial Ischemia
Cardiac Output
Increased in
Congestive Heart Failure
Decreased or normal if no
Heart Failure
Arterial Dilation (less than
Nitroprusside
)
Relieves
Angina
Dilates large coronary arteries
Antagonizes vasospasm
Increases coronary collateral
Blood Flow
Increases perfusion to ischemic
Myocardium
Decreases systemic vascular resistance
Esophageal Spasm
also responds to nitrates
Pain relief with Nitroglycerin is not always
Angina
Drug Interactions
Phosphodiesterase Inhibitor
s (e.g.
Viagra
or
Sildenafil
)
Profound hypotensive reaction
Do not use with Nitroglycerin!
Nitrates may be used >24 hours after
Sildenafil
or vardenafil or >48 hours after
Tadalafil
Tissue Plasminogen Activator (
Alteplase
, tPA)
IV Nitroglycerin may reduce plasma concentrations
Heparin
IV Nitroglycerin may reduce
Anticoagulant
response
Adverse Effects
Headache
Hypotension
High risk with
Aortic Stenosis
,
Pulmonary Hypertension
,
Hypotension
,
PDE5 Inhibitor
, right-sided
Myocardial Infarction
Reduce Nitrate dose
Administer
Intravenous Fluid
bolus
Consider
Atropine
if
Bradycardia
present
Methemoglobinemia
Hypoxemia
(Ventilation-perfusion mismatch)
References
Orman and Mattu in Herbert (2017) EM:Rap 17(7): 6-7
Type your search phrase here