You have a patient with achalasia (incomplete muscle relaxation of the GI tract, especially sphincter muscles). Which medications do you anticipate to administer?
A. isosorbide dinitrate (Isordil)
B. digoxin (Lanoxin)
C. captopril (Capoten)
D. propranolol (Inderal)
Correct Answer: A. isosorbide dinitrate (Isordil)
Achalasia is characterized by incomplete relaxation of the LES, dilation of the lower esophagus, and a lack of esophageal peristalsis. Because nitrates relax the lower esophageal sphincter, expect to give Isordil orally or sublingually. Isosorbide is a nitrate that exerts its pharmacologic effect by releasing nitric oxide (NO), an endothelium-derived relaxing factor (EDRF).NO is endogenously produced in the endothelium to dilate the blood vessels.
Option B: Digoxin is a medication used in the management and treatment of heart failure and certain arrhythmias and abortion. It is in the cardiac glycoside class of drugs. It is used for rate control in atrial fibrillation or atrial flutter when conventional therapies have not achieved goal heart rate. Digoxin should not be administered in cases of pre-excitation caused by accessory pathways as digoxin induces AV blockade and may trigger ventricular tachyarrhythmias.
Option C: The benefits of captopril in hypertension and heart failure result primarily from suppressing the renin-angiotensin-aldosterone system (RAAS). As an angiotensin-converting enzyme (ACE) inhibitor, it inhibits ACE, which converts angiotensin I to angiotensin II. Angiotensin II binds to AT1 receptors on smooth muscles to produce vasoconstriction of precapillary arterioles and postcapillary venules, inhibits the reuptake of norepinephrine, and release of catecholamines from the adrenal medulla, which all increases blood pressure.
Option D: Propranolol can be used to ameliorate the sympathetic response in angina, tachyarrhythmias, prevention of acute ischemic attacks, migraine prophylaxis, and restless leg syndrome. Propranolol can be used in almost all cases if the desired result is to slow contractility and decrease a patient’s heart rate.
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