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Nitrate tolerance. How to prevent it or minimize its effect

U Thadani1

  • 1Cardiology Section, University of Oklahoma Health Sciences Center, Oklahoma City 73104.

Postgraduate Medicine
|April 1, 1992
PubMed

Insights

Nitrate tolerance diminishes antianginal effects. Intermittent nitrate use or combination therapy can prevent tolerance in stable angina. Continuous intravenous nitroglycerin is used for unstable angina.

Area of Science:

  • Cardiology
  • Pharmacology

Background:

  • Continuous nitrate therapy leads to rapid tolerance, reducing circulatory, antianginal, and anti-ischemic effects.
  • Nitrate tolerance is a significant clinical challenge in managing angina and heart failure.

Purpose of the Study:

  • To review strategies for avoiding or managing nitrate tolerance.
  • To outline appropriate nitrate use in stable angina, unstable angina, and congestive heart failure.

Main Methods:

  • Review of existing literature on nitrate therapy and tolerance.
  • Analysis of different dosing regimens and combination therapies for angina management.

Main Results:

  • Intermittent nitrate use with nitrate-free intervals is effective for stable angina.
  • Transdermal nitroglycerin or specific oral nitrate regimens can mitigate tolerance.
  • Intravenous nitroglycerin is recommended for acute unstable angina.
  • Oral isosorbide dinitrate plus hydralazine may benefit heart failure patients with ACE inhibitor intolerance.

Conclusions:

  • Nitrate tolerance can be effectively managed through strategic dosing and combination therapies.
  • Specific approaches are recommended for stable angina, unstable angina, and heart failure.
  • Concomitant use of sulfhydryl donors or ACE inhibitors to prevent tolerance is not currently recommended due to conflicting data and potential adverse effects.

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