Does hydralazine affect renal function?

From the Guidelines

Hydralazine can affect renal function, particularly in patients with pre-existing renal insufficiency or chronic kidney disease (CKD), as it is renally excreted and can accumulate in these patients 1.

Key Points

• Hydralazine can increase renal arterial flow due to its vasodilatory effects, which may be beneficial in certain cases 1.
• However, it can also cause drug-induced lupus, which can involve the kidneys and lead to renal dysfunction 1.
• The combination of hydralazine and isosorbide dinitrate has been shown to reduce mortality in patients with heart failure, including those with renal failure 1.
• Hydralazine is contraindicated in patients with bilateral renal artery stenosis 1.
• Patients with CKD may require dose adjustments when taking hydralazine, and monitoring of renal function is recommended 1.

Important Considerations

• Hydralazine should be used with caution in patients with renal impairment, and the benefits and risks of treatment should be carefully weighed 1.
• Regular monitoring of renal function and electrolyte levels is essential when using hydralazine, especially in patients with pre-existing kidney disease 1.

From the FDA Drug Label

In hypertensive patients with normal kidneys who are treated with hydrALAZINE, there is evidence of increased renal blood flow and a maintenance of glomerular filtration rate. In some instances where control values were below normal, improved renal function has been noted after administration of hydrALAZINE However, as with any antihypertensive agent, hydrALAZINE should be used with caution in patients with advanced renal damage.

Hydralazine may affect renal function, but the overall effect is variable. In patients with normal kidneys, hydralazine may increase renal blood flow and maintain glomerular filtration rate. In some cases, it may even improve renal function. However, in patients with advanced renal damage, hydralazine should be used with caution 2.

From the Research

Effects of Hydralazine on Renal Function

• Hydralazine can affect renal function, as evidenced by a decrease in glomerular filtration rate (GFR) correlated with an increase in serum half-life of the drug 3.
• The renal excretion of hydralazine is generally regarded as unimportant, and the slower elimination rate in chronic renal failure is probably caused by a slower rate of metabolic conversion 3.
• Hydralazine can cause severe acute kidney injury (AKI) resulting in chronic kidney disease (CKD) or death, particularly in patients with pre-existing renal impairment 4.
• Low-dose hydralazine has been shown to prevent fibrosis in a murine model of AKI-to-CKD progression, suggesting a potential protective effect on renal function 5.

Renal Outcomes in Hydralazine-Induced Vasculitis

• Hydralazine-induced vasculitis frequently affects the kidney, and renal involvement can be associated with a poor renal outcome despite immunosuppressive therapy 6.
• A retrospective cohort study found that 71% of patients with hydralazine-induced ANCA-associated vasculitis had renal involvement, and three patients reached end-stage renal disease 6.
• Another study found that hydralazine treatment was associated with a significantly higher risk of developing renal disease in men, and severe weight loss in women 7.

Comparison with Other Treatments

• A comparison of hydralazine with methyldopa treatment found similar risk factors for cardiovascular disease, but no significant differences in morbidity or mortality between the two groups 7.
• The study also found that the risk of renal disease was higher in patients treated with hydralazine, particularly in men, although this may be due to poorer renal function and higher untreated blood pressure at presentation 7.