Adrenergic blockers

Alpha-blockers

Fainting (syncope) with the first dose, awareness of rapid heartbeats (palpitations), dizziness, low blood pressure when the person stands (orthostatic hypotension), and fluid retention (edema)

Beta-blockers

8. Penbutolol

With some beta-blockers, an increased triglyceride level

Alpha-beta blockers

Low blood pressure when the person stands and spasm of the airways

Angiotensin-converting enzyme (ACE) inhibitors

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Cough (in up to 20% of people), low blood pressure, an increased potassium level, rash, angioedema (allergic swelling that affects the face, lips, and windpipe and may interfere with breathing), and, in pregnant women, serious injury to the fetus

Angiotensin II receptor blockers (ARBs)

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3. Eprosartan

Dizziness, an increased potassium level, angioedema (rarer than with ACE inhibitors), and, in pregnant women, serious injury to the fetus

Calcium channel blockers

Dihydropyridines

Dizziness, fluid retention in the ankles, flushing, headache, heartburn, enlarged gums, and an abnormally fast heart rate (tachycardia)

Nondihydropyridines

Headache, dizziness, flushing, fluid retention, problems in the heart's electrical conduction system (including heart block), an abnormally slow heart rate (bradycardia), heart failure, and enlarged gums

Centrally acting alpha-agonists

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2. Guanabenz

Direct vasodilators

—

Headache, an abnormally fast heart rate (tachycardia), and fluid retention

Diuretics

Loop diuretics

Decreased levels of potassium and magnesium, temporarily increased levels of blood sugar and cholesterol, an increased level of uric acid, sexual dysfunction in men, and digestive upset

Potassium-sparing diuretics

With all, a high potassium level and digestive upset

Thiazides and thiazide-like diuretics

1. Bendroflumethiazide

5. Hydroflumethiazide

Decreased levels of potassium and magnesium, increased levels of calcium and uric acid, sexual dysfunction in men, and digestive upset