From the Guidelines
Hydralazine is associated with peripheral edema due to its effects on sodium and water retention.
Key Points
- The usual dose of hydralazine is 100-200 mg/day, administered 2 or 3 times a day 1.
- Hydralazine is a direct vasodilator that can cause reflex tachycardia and sodium and water retention, leading to peripheral edema 1.
- To mitigate these effects, hydralazine is often used in combination with a diuretic and beta blocker 1.
- Additionally, hydralazine can cause drug-induced lupus-like syndrome at higher doses 1.
- The association of hydralazine with peripheral edema is a well-established side effect, and clinicians should be aware of this potential complication when prescribing the medication.
From the Research
Hydralazine and Peripheral Edema
- Hydralazine is a direct-acting vasodilator that has been associated with peripheral edema, particularly vasodilatory edema 2
- Vasodilatory edema is a common adverse effect of antihypertensive therapy with vasodilators, and is related to several mechanisms, including arteriolar dilatation and fluid volume retention 2
- The incidence of vasodilatory edema with hydralazine is dose-dependent, and is more common with direct arteriolar dilators such as minoxidil or hydralazine 2
- Other studies have reported various adverse effects associated with hydralazine, including reflex tachycardia, hemolytic anemia, vasculitis, glomerulonephritis, and a lupus-like syndrome 3, but do not specifically mention peripheral edema
- A review of drug-induced peripheral edema mentions that many drugs, including vasodilators, can cause peripheral edema through different mechanisms, but does not specifically discuss hydralazine 4
Mechanisms and Treatment
- The underlying mechanism of peripheral edema has a significant impact on treatment efficacy, and understanding the pathophysiological mechanism is crucial for effective management 4
- The addition of an angiotensin-converting enzyme (ACE) inhibitor or an angiotensin receptor blocker (ARB) to a dihydropyridine calcium antagonist can significantly reduce vasodilatory edema, while the addition of a diuretic has little effect 2
- Low-dose combination therapy (of a dihydropyridine calcium antagonist with either an ACE inhibitor or an ARB) may be preferred over high-dose monotherapy to minimize the risk of vasodilatory edema 2