Comment
Author: Admin | 2025-04-28
Is more useful to reduce the preload of the heart and this is accomplished with NITRATES, which decrease the venous return to the heart. Beta blockers and Ca++ channel blockers can be used in the prophylaxis of exertional angina, but the quick onset of the nitrates makes drugs like nitroglycerine more effective for treating an acute exertional angina.You gave too high a dose of nitroglycerine or isosorbide mononitrate to a patient and his angina worsened. Why is this?Nitrates cause vasodilation. Giving an excessive dose causes systemic vasodilation, which will result in reflex tachycardia by the baroreceptor mechanism. Increased heart rate increases the workload and O2 demand of the heart! (this is exactly what you don't want in a patient with angina)If you withdraw nitrates suddenly, what could result?Myocardial infarction or sudden death can result from sudden nitrate withrawal. This is because the body can undergo dependence during nitrate therapy. Nitrates also show tachyphylaxis, a quick tolerance development that can also be lost rapidly. This is important in developing a treatment regimen.What are side-effects of nitrates?Remember that nitrates cause vasodilation. This accounts for many of their side-effects: Headache: from vasodilation of meningeal vesselsPostural hypotension: due to systemic vasodilationSyncope: from postural hypotensionIsosorbide mononitrate should not be accompanied by administration of what other drug?Isosorbide mononitrate is a nitrate drug used to treat angina. It causes hypotension due to vasodilation. Sildenafil (Viagra) is a cGMP phosphodiesterase inhibitor. It can cause life threatening hypotension if given with nitrates. This is because the extreme hypotension will cause reflex tachycardia and precipitate a myocardial infarction. In people with angina, this tachycardia increases the heart's O2 demand. This is exactly what you don't want! Remember that nitrates increase cGMP levels to cause hypotension.Nitroglycerine is another nitrate commonly used.Which antianginal drugs should not be used in patients with hypertrophic
Add Comment