Hydralazine use can be associated with IgM-dominated immune complex-mediated glomerulonephritis.

CONTEXT: IgM-dominant immune complex-mediated glomerulonephritis (IgM-dominant ICMGN) is a rare renal entity, characterized by a membranoproliferative pattern by light microscopy, dominant IgM staining by immunofluorescent staining, and subendothelial deposits by electron microscopy. This study was to investigate if some of IgM-ICMGN were associated with autoimmune disorders induced by hydralazine. DESIGN: Seven IgM-dominant ICMGN cases were identified over 8 years. Their pathologic phenotypes and clinical scenarios were analyzed in detail. RESULTS: Patients' ages ranged from 47 to 87 years old with 5 women and two men. Six of seven patients had drug-induced autoimmune phenomenon (hydralazine-induced positive ANCA and ANA). All of them had renal dysfunction and some proteinuria. Most pathologic features showed a membranoproliferative pattern of glomerulonephritis with dominant IgM deposits at subendothelial spaces. IgM nephropathy (a variant of focal segmental glomerulosclerosis), chronic thrombotic microangiopathy, and cryoglobulinemic glomerulopathy were ruled out in the cases. CONCLUSION: The hydralazine-induced autoimmune phenomenon can be seen in IgM-dominant ICMGN, which should be classified as a subtype of membranoproliferative glomerulonephritis.

The Effects of Verapamil, Hydralazine, and Doxazosin on Renin, Aldosterone, and the Ratio Thereof.

PURPOSE: Hydralazine, doxazosin, and verapamil are currently recommended by the Endocrine Society as acceptable bridging treatment in those in whom full cessation of antihypertensive medication is infeasible during screening for primary aldosteronism (PA). This is under the assumption that they cause minimal to no effect on the aldosterone-to-renin ratio, the most widely used screening test for PA. However, limited evidence is available regarding the effects of these particular drugs on said ratio. METHODS: In the present study, we retrospectively assessed the changes in aldosterone, renin, and aldosterone-to-renin values in essential hypertensive participants before and after treatment with either hydralazine (n = 26) or doxazosin (n = 20) or verapamil (n = 15). All samples were taken under highly standardized conditions. RESULTS: Hydralazine resulted in a borderline significant rise in active plasma renin concentration (19 vs 25 mIU/L, p = 0.067) and a significant fall in the aldosterone-to-renin ratio (38 vs 24, p = 0.017). Doxazosin caused declines in both plasma aldosterone concentration (470 vs 330 pmol/L, p = 0.028) and the aldosterone-to-renin ratio (30 vs 20, p = 0.020). With respect to verapamil, we found no statistically significant effect on any of these outcome variables. CONCLUSION: We conclude that the assumption that these drugs can be used with little consequence to the aldosterone-to-renin cannot be substantiated. While it is possible that they are indeed the best option when full antihypertensive drug cessation is infeasible, the potential effects of these drugs must still be taken into account when interpreting the aldosterone-to-renin ratio.

Anti-neutrophil cytoplasmic antibody associated glomerulonephritis complicating treatment with hydralazine.

Hydralazine, a widely used therapy for hypertension and heart failure, can elicit autoimmune disease, including anti-neutrophil cytoplasmic antibody associated glomerulonephritis (ANCA-GN). We identified 80 cases of ANCA-GN complicating treatment with hydralazine, accounting for 4.3% (80/1858 biopsies) of ANCA-GN diagnosed between 2006 and 2019. Over three-fourths of patients were on hydralazine for at least one year, with mean daily dose of approximately 250 mg/day. ANCA testing revealed p-ANCA/myeloperoxidase-ANCA seropositivity in 98%, including 39% with dual p-ANCA/myeloperoxidase-ANCA and cANCA/anti-protinase 3-ANCA positivity, often accompanied by anti-nuclear antibody (89%), anti-histone antibody (98%), and hypocomplementemia (58%). Kidney biopsy revealed necrotizing and crescentic glomerulonephritis, similar to primary ANCA-GN, but significantly less frequently pauci-immune (77 vs. 100%) and more commonly associated with mesangial hypercellularity (30 vs. 5%), electron dense deposits (62 vs. 20%), and endothelial tubuloreticular inclusions (11 vs. 0%); all significant differences. On follow-up, 42 of 51 patients received induction immunosuppression: 19 reached the combined end-points of kidney failure or death and 32 had mean creatinine of 1.49 mg/dL at last follow-up. Thus, hydralazine-associated ANCA-GN often exhibits overlapping clinical and pathologic features of mild immune complex glomerulonephritis resembling lupus nephritis. With discontinuation of hydralazine and immunosuppression, outcomes are similar to primary ANCA-GN.

Safety and efficacy of intravenous hydralazine and labetalol for the treatment of asymptomatic hypertension in hospitalised patients: A systematic review.

BACKGROUND: Current guidelines for the management of asymptomatic hypertension (HTN) in the inpatient setting recommend the use of oral antihypertensives. However, in clinical practice, intravenous (IV) antihypertensives are commonly utilised with little supporting evidence. The objective of this study was to evaluate literature examining the safety/efficacy of IV hydralazine and labetalol in hospitalised patients with non-emergent, asymptomatic HTN. METHODS: The PRISMA guidelines were utilised to structure the systematic review. A search strategy composed of drug-, inpatient- and HTN-related terms was conducted utilising PubMed, Embase and Scopus databases through May 2020. Full-text, English-language articles describing IV labetalol and/or hydralazine use for non-emergent HTN in an inpatient setting that focused on clinical outcomes (ie vitals, adverse effects, healthcare utilisation) were included. Identified studies were screened/extracted using DistillerSR by two reviewers at each stage, and studies were evaluated qualitatively for the presence of bias. RESULTS: From 3362 records identified in the search, a final set of 10 articles were identified. Four studies focused on labetalol (40%), five studies on hydralazine and labetalol (50%), and one study on hydralazine (10%). The included studies presented a variety of outcomes, but several trends were identified, including reduction in average blood pressure in eight (80%) studies, a risk of adverse effects in six (60%) and increased length of stay in one (10%). DISCUSSION: The studies identified in this review raise concerns regarding the safety of IV hydralazine and labetalol in non-emergent HTN. Despite relatively broad clinical experience with these drugs, experimental investigations regarding their utility are recommended.

Severe hydralazine-induced lupus presenting as systemic lupus erythematosus.

Despite its long history of untoward side effects of a systemic autoimmune disease, drug-induced lupus can be difficult to recognize because of the disconnect between chronic drug usage and onset of symptoms. In this case, the patient was treated with hydralazine for two years when symptoms were initially reported, but a diagnosis of hydralazine-induced lupus was not considered for another half year. Despite treatment with steroidal and nonsteroidal anti-inflammatory medications during this period, rheumatologic symptoms and signs continued to deteriorate, consistent with the diagnosis of systemic lupus erythematosus. Not until the patient voluntarily discontinued hydralazine did symptoms begin to improve, fully resolving over the subsequent 6-12 months largely in the absence of anti-inflammatory medication. This patient demonstrates that failure to recognize a drug-induced disease etiology can result in substantial worsening of rheumatologic symptoms over the subsequent six months, ultimately satisfying criteria for systemic lupus erythematosus. While symptoms and signs largely normalized, some laboratory abnormalities and occasional arthralgia remained two years after discontinuing hydralazine, suggesting smoldering inflammatory disease.

Drug-induced systemic lupus: revisiting the ever-changing spectrum of the disease using the WHO pharmacovigilance database.

OBJECTIVE: Drug-induced lupus (DIL) is an idiosyncratic side effect of treatments in which symptoms overlap with those of systemic lupus erythematosus (SLE). The spectrum of DIL constantly evolves with that of the pharmacopoeia. Here, we used VigiBase, the WHO global individual case safety reports (ICSRs) database, to identify the main drugs associated with DIL. METHODS: We analysed all ICSRs classified as 'systemic lupus erythematosus' according to the Medical Dictionary for Drug Regulatory Activities term (preferred term level) in VigiBase. The drugs considered in the analysis were those not used to treat SLE, with a positive lower end of the 95% credibility interval for the information component (IC025) ≥0, an indicator value for disproportionate Bayesian reporting. RESULTS: A total of 12 166 DIL ICSRs were identified using VigiBase. From those, 8163 ICSRs reporting on 118 suspected drugs with IC025 ≥0 were extracted. The median age at DIL onset was 49 years and the female to male sex ratio was 4.3. The median delay between start of suspected treatment and DIL occurrence was 172 days. DIL was reported as serious adverse event in 55.4%. Among the 118 suspected drugs, 42 had not been previously reported in association with DIL. The drugs associated with the highest number of DIL cases were infliximab, adalimumab, etanercept, procainamide and hydralazine. CONCLUSION: This study enables the identification of 118 drugs associated with DIL. The list of suspected drugs may prove useful to physicians when confronted with potential DIL cases. TRIAL REGISTRATION NUMBER: NCT03480529.

Neonatal hypertension: cases, causes, and clinical approach.

Neonatal hypertension is increasingly recognized as dramatic improvements in neonatal intensive care, advancements in our understanding of neonatal physiology, and implementation of new therapies have led to improved survival of premature infants. A variety of factors appear to be important in determining blood pressure in neonates, including gestational age, birth weight, and postmenstrual age. Normative data on neonatal blood pressure values remain limited. The cause of hypertension in an affected neonate is often identified with careful diagnostic evaluation, with the most common causes being umbilical catheter-associated thrombosis, renal parenchymal disease, and chronic lung disease. Clinical expertise may need to be relied upon to decide the best approach to treatment in such patients, as data on the use of antihypertensive medications in this age group are extremely limited. Available data suggest that long-term outcomes are usually good, with resolution of hypertension in most infants. In this review, we will take a case-based approach to illustrate these concepts and to point out important evidence gaps that need to be addressed so that management of neonatal hypertension may be improved.

Hyperbaric oxygen therapy for perioperative posterior ischemic optic neuropathy: a case report.

PURPOSE: To report the successful treatment of postoperative posterior ischemic optic neuropathy (PION) with hyperbaric oxygen therapy and to review the current literature on the pathogenesis and treatment of PION. OBSERVATIONS: During an angiographic procedure at a community hospital, an elderly woman had a transient drop in blood pressure after receiving an intravenous dose of hydralazine. During recovery, the patient experienced bilateral vision loss. She was transferred to our specialty referral center for treatment with hyperbaric oxygen. We followed Table 5 in the U.S. Navy Diving Manual, the protocol for decompression sickness. Our patient's vision improved markedly immediately after the first session and continued to improve throughout the course of treatment to its completion. Follow-up ophthalmology visits found the patient's vision to be close to baseline. CONCLUSIONS AND IMPORTANCE: PION is a rare condition. It has been difficult to determine a successful therapeutic approach because of the lack of large case-controlled studies. Hyperbaric oxygen has been used to treat other ischemic ophthalmic conditions, but there are only few reports of its use in patients with PION. Systemic steroids and antiplatelet therapy have also been used, with mixed success. In our patient, the combination of hyperbaric oxygen therapy and steroids was successful in restoring vision after postoperative PION.

Drug-induced lupus erythematosus: an update on drugs and mechanisms.

PURPOSE OF REVIEW: Rapid introduction of newly developed drugs in the absence of clear understanding of the pathophysiologic mechanisms behind drug-induced lupus erythematosus (DILE) can sometimes make DILE difficult to recognize in clinical practice. The purpose of this review is to summarize drugs most recently reported to be involved in DILE and discuss the current landscape of diverse mechanisms involved. RECENT FINDINGS: A large number of proton pump inhibitor (PPI)-induced subacute cutaneous lupus erythematosus cases have been reported, suggesting a shift over time in the spectrum of drugs implicated in DILE. Twenty-two articles comprising 29 DILE case reports published within the last 2 years are summarized in this review, including 12 (41.4%) systemic DILE. Antitumor necrosis factor (anti-TNF) drugs were the most frequently (41.7%) reported to introduce systemic DILE in these cases. Chemotherapeutic drugs were the most common drug class (54.5%) involved in subacute cutaneous lupus erythematosus, with an observed higher incidence in female patients. Enhanced neutrophil extracellular trap (NET) formation induced by procainamide and hydralazine could be a new mechanism contributing to the pathogenesis of DILE. SUMMARY: The list of drugs implicated in triggering DILE is expanding as new drugs with novel mechanisms of action are being developed. It is important to recognize culprit drugs that may induce lupus erythematosus, as discontinuation usually results in improvement of drug-induced manifestations. Characterizing the mechanisms involved might help better understand the cause of idiopathic autoimmunity.

Drugs for treating severe hypertension in pregnancy: a network meta-analysis and trial sequential analysis of randomized clinical trials.

AIMS: Several antihypertensive drugs are used in the treatment of severe hypertension in pregnancy. The present study is a network meta-analysis comparing the efficacy and safety of these drugs. METHODS: Electronic databases were searched for randomized clinical trials comparing drugs used in the treatment of severe hypertension in pregnancy. The number of women achieving the target blood pressure (BP) was the primary outcome. Doses required and time taken for achieving the target BP, failure rate, and incidences of maternal tachycardia, palpitation, hypotension, headache, and neonatal death and stillbirth were the secondary outcomes. Mixed treatment comparison pooled estimates were generated using a random-effects model. Odds ratios for the categorical and mean difference for the numerical outcomes were the effect estimates. RESULTS: Fifty-one studies were included in the systematic review and 46 in the meta-analysis. No significant differences in the number of patients achieving target BP was observed between any of the drugs. Diazoxide [-15 (-20.6, -9.4)], nicardipine [-11.8 (-22.3, -1.2)], nifedipine/celastrol [-19.3 (-27.4, -11.1)], nifedipine/vitamin D [-17.1 (-25.7, -9.7)], nifedipine/resveratrol [-13.9 (-22.6, -5.2)] and glyceryl trinitrate [-33.8 (-36.7, -31)] were observed to achieve the target BP (in minutes) more rapidly than hydralazine. Nifedipine required fewer doses than hydralazine for achieving the target BP. Glyceryl trinitrate and labetalol were associated with fewer incidences of tachycardia and palpitation respectively than hydralazine. Trial sequential analysis concluded adequate evidence for hydralazine and nifedipine compared with labetalol. Moderate quality of evidence was observed for direct comparison estimate between labetalol and hydralazine but was either low or very low for other comparisons. CONCLUSION: The present evidence suggests similar efficacy between nifedipine, hydralazine and labetalol in the treatment of severe hypertension in pregnancy. Subtle differences may exist in their safety profile. The evidence is inadequate for other drugs.

Incidence, Course, and Characteristics of Hydralazine-Associated Tachycardia During Phase I Postanesthesia Recovery.

PURPOSE: This study aims to characterize the development of tachycardia after intravenous hydralazine administration during Phase I recovery. DESIGN: Retrospective observational study design. METHODS: The medical records of 745 adult surgical patients who were administered hydralazine during Phase I recovery between January 1, 2010 and December 31, 2014 were electronically reviewed to characterize episodes of tachycardia. FINDINGS: Seventy patients (94.0 cases per 1,000 administrations; 95% confidence interval = 74.0 to 117.2) developed tachycardia with a median increase of 23 beats per minute (bpm; interquartile range [IQR] = 15 to 37), a maximum rate of 106 bpm (IQR = 103 to 111; range = 101 to 131), and duration of 28 minutes (IQR = 5 to 86). The median onset of tachycardia was 43 minutes (IQR = 20 to 93), with 40% occurring after the first hour. Tachycardia was associated with female sex (P < .001), younger age (P < .001), and those with lesser comorbidities (P < .009). CONCLUSIONS: A sizeable proportion of cases of tachycardia associated with hydralazine administration occurred after 1 hour, suggesting that these patients who may not tolerate a faster heart rate warrant longer duration of monitoring.

Intravenous Hydralazine in Hospitalized Children and Adolescents with Hypertension.

OBJECTIVES: To explore the efficacy and safety of intravenous (IV) hydralazine in hospitalized children with hypertension. STUDY DESIGN: Data were retrospectively collected on hospitalized children treated with IV hydralazine. Percent changes in blood pressure (BP) were calculated, and linear regression was used to investigate associations between BP change and pertinent clinical and demographic variables. Bivariate logistic regression was used to investigate associations between the same covariates and the outcomes of ideal clinical response (ICR), a 10%-25% reduction in mean arterial pressure (MAP), and excess response (ER), a 25% reduction in MAP. RESULTS: A total of 141 initial doses of IV hydralazine (median dose, 0.10 mg/kg [IQR, 0.09-0.11; range, 0.02-0.37]) were analyzed. Median age was 8 years (IQR, 2-15; range, 0-24); most patients had renal disease, malignancy, or were organ transplant recipients. The mean MAP reduction was 19% ± 12%. An ICR occurred in 66 patients (47%). Higher initial MAP and increased hydralazine dose were associated with greater percentage decrease in MAP. No association was found between ICR and the covariates of interest; higher initial MAP was associated with greater odds of ICR. ER occurred in 44 children (31%). Among this group, higher initial MAP and higher hydralazine dose were associated with increased odds of ER, and administration of other antihypertensive drugs was associated with decreased odds of ER. Four adverse effects possibly related to IV hydralazine, including 2 episodes of hypotension, were recorded. CONCLUSIONS: IV hydralazine reduced BP in the majority of children. However, a substantial proportion of children experienced potentially excessive BP reduction.

Acute Cholestatic Liver Injury From Hydralazine Intake.

Hydralazine is a commonly used oral antihypertensive agent. We report a rare case of hydralazine-induced hepatotoxicity in the form of subacute hepatic necrosis. A 75-year-old African American woman presented with jaundice of 7-day duration. She was started on hydralazine 100 mg 3 times a day 10 weeks before presentation. On physical examination, scleral icterus was noted. Workup revealed elevated liver transaminases, alkaline phosphatase, and conjugated bilirubin. She had no history of liver disease, and liver function tests had been normal before starting hydralazine. Other etiologies, including viruses, common toxins, drugs, autoimmune, and copper-induced hepatitis, were excluded. Abdominal imaging studies did not show any evidence of intrahepatic or extrahepatic biliary ductal dilatation, and no pathologies were seen in the liver and pancreas. The patient's liver biopsy revealed extensive lobular hepatitis, significant necrosis, mixed inflammatory infiltrate, and no significant fibrosis, supporting a diagnosis of drug-induced liver injury. Hydralazine was immediately discontinued. She showed improvement of clinical and laboratory abnormalities within 5 days after discontinuation of hydralazine. To establish the diagnosis of hydralazine-induced liver injury, we used assessment tool outlined by the Council for International Organization of Medical Sciences (CIOMS) scale that led to "high probable" relationship. Although rare, clinically significant, and potentially life-threatening liver injury can result from use of hydralazine. Both clinical and histological presentations in our patient suggest acute liver injury. The hydralazine-induced hepatitis seems to be reversible as discontinuation of the drug improves clinical outcomes. We highly recommend monitoring of the liver function during hydralazine treatment.

A One-Two Punch: Hydralazine-Induced Liver Injury in a Recovering Ischemic Hepatitis.

A 77-year-old woman presented to the emergency department with a 2-day history of nausea and vomiting. Her medical history included diabetes mellitus, hypertension, atrial fibrillation, dilated cardiomyopathy, and coronary artery disease. Her home medications included aspirin, clopidogrel, warfarin, digoxin, metoprolol, losartan, simvastatin, isosorbide dinitrate, furosemide, and spironolactone. Initial physical examination showed blood pressure of 170/80 mm Hg with a heart rate of 69 beats per minute, otherwise unremarkable. Initial laboratory workup was significant for INR of 3.6, with slightly elevated troponin I and creatinine of 0.06 ng/mL and 1.4 mg/dL, respectively. The patient was admitted to the medicine floor. However, a few hours later, her atrial fibrillation went into rapid ventricular response, associated with hypotension. Cardiac enzymes began to trend up along with worsening of her renal function tests and hepatic enzymes. Her INR remained supratherapeutic despite holding coumadin and giving vitamin K. The patient was transferred to the medical intensive care unit for closer monitoring. During day 1 of the medical intensive care unit stay, losartan, simvastatin, and diuretics were held, whereas aspirin, clopidogrel, and isosorbide dinitrate were continued. In the following 2 days, there was worsening of tissue perfusion, and laboratory workup showed AST 514 IU/L, ALT 391 IU/L, INR >9, creatinine 3.8 mg/dL, and troponin I 0.19 ng/mL; therefore, digoxin was also held. Once the patient achieved hemodynamic stability, she was started on hydralazine. On day 4, renal function, cardiac, and hepatic enzymes improved significantly. However, 24 hours later, transaminases began to trend up again reaching a maximum of AST and ALT of 359 and 525 IU/L, respectively. Other possible causes were ruled out because her viral hepatitis markers, antihistone antibody, antinuclear antibody, and anti-double-stranded DNA were all negative. After thorough review of all medications, hydralazine was held with subsequent improvement in transaminases. The patient was seen a month later after her discharge, and all her laboratory workup improved to baseline.

Drug-induced liver injury with autoimmune features.

Drug-induced liver injury (DILI) with features of autoimmunity (AI) represents an important category of hepatotoxicity due to medication exposure. Drugs repeatedly associated with AI-DILI include diclofenac, α-methyl DOPA, hydralazine, nitrofurantoin, minocycline, and more recently statins and anti-TNF-α agents. Usually, symptoms of acute liver injury occur within a few months after initiation of a culprit medication, but a longer latency period is possible. Like idiopathic autoimmune hepatitis, circulating autoantibodies and a hypergammaglobulinemia are frequently present in sera from patients with AI-DILI. If performed, a liver biopsy should demonstrate interface hepatitis with a prominent plasma cell infiltrate. The severity of AI-DILI is variable, but a complete resolution after withdrawal of the offending medication is the expectation. A response to corticosteroid therapy supports the diagnosis, whereas a lack of recurrence of symptoms or signs following corticosteroid cessation distinguishes AI-DILI from idiopathic autoimmune hepatitis.

Trojan horses: drug culprits associated with antineutrophil cytoplasmic autoantibody (ANCA) vasculitis.

PURPOSE OF REVIEW: Antineutrophil cytoplasmic autoantibody (ANCA) vasculitis is a systemic autoimmune disease resulting in small-vessel inflammation caused by pathogenic autoantibodies directed against proteinase 3 or myeloperoxidase. Legal drug culprits have been implicated as causative agents in secondary forms of disease, and a recent burst of reports also implicate levamisole-adulterated cocaine as a culprit. RECENT FINDINGS: Here, we briefly discuss all drug culprits associated with ANCA vasculitis and then focus on clinical, serologic, therapeutic and mechanistic aspects of four main drug culprits receiving attention of late, namely hydralazine, minocycline, propylthiouracil (PTU) and levamisole-adulterated cocaine. SUMMARY: Hydralazine, minocycline, propylthiouracil and levamisole-adulterated cocaine use should be closely considered in any patient where ANCA vasculitis is entertained given the wide use of these drugs in the community. Furthermore, medical practitioners should test urine for the presence of cocaine in any patient with presumed ANCA vasculitis, and if positive, then urine should also be tested for levamisole. Clinical features can be severe requiring not only drug cessation and supportive care, but also immunosuppression, plasma exchange in severe cases and dialysis as needed. Clinical trial investigators should strongly consider excluding patients with drug-induced forms of disease and mechanistic inroads are greatly needed in these secondary forms of disease to help elucidate the underlying cause and pathogenesis of ANCA vasculitis.

Diagnosis and classification of drug-induced autoimmunity (DIA).

Since sulfadiazine associated lupus-like symptoms were first described in 1945, certain drugs have been reported to interfere with the immune system and induce a series of autoimmune diseases (named drug-induced autoimmunity, DIA), exemplified by systemic lupus erythematosus (SLE). Among the drugs, procainamide and hydralazine are considered to be associated with the highest risk for developing lupus, while quinidine has a moderate risk, and all other drugs have low or very low risk. More recently, drug-induced lupus has been associated with the use of newer biological modulators, such as tumor necrosis factor (TNF)-alpha inhibitors and cytokines. In addition to lupus, other major autoimmune diseases, including vasculitis and arthritis, have also been associated with drugs. Because resolution of symptoms generally occurs after cessation of the offending drugs, early diagnosis is crucial for treatment strategy and improvement of prognosis. Unfortunately, it is difficult to establish standardized criteria for DIA diagnosis. Diagnosis of DIA requires identification of a temporal relationship between drug administration and the onset of symptoms, but the relative risk with respect to dose and duration for each drug has rarely been determined. DIA is affected by multiple genetic and environmental factors, leading to difficulties in establishing a list of global clinical features that are characteristic of most or all DIA patients. Moreover, the distinction between authentic DIA and unmasking of a latent autoimmune disease also poses challenges. In this review, we summarize the highly variable clinical features and laboratory findings of DIA, with an emphasis on the diagnostic criteria.

The efficacy and safety of intravenous hydralazine for the treatment of hypertension in the hospitalized child.

BACKGROUND: Intravenous (IV) hydralazine is frequently used for the treatment of elevated blood pressure (BP) in hospitalized children. Its safety and efficacy have not been examined. METHODS: This is a retrospective chart review of IV hydralazine use in hospitalized children (birth to 17 years) over a 3-year period. Demographic data and data on adverse effects (AE), BP, and heart rate (HR) prior to and after each first dose were collected. RESULTS: The patient cohort comprised 110 children admitted to the hospital during the study period, of whom 77 received the recommended dose. Mean age of the children was 8.5 ± 5.4 years; 33 % were male, and 32.5 % were white. Pre-dose systolic and diastolic BP indexes were 1.3 and 1.2, respectively. The median reduction in systolic and diastolic BP was 8.5 and 11.5 %, respectively. Sixteen (21 %) children achieved a 25 % reduction in systolic or diastolic BP, and BP increased in 30 % of patients; 10 % of children had a BP of <95th percentile for age, sex, and height after one dose. Seven (9 %) children had a documented AE. HR increased by a median of 3.5 %. In the multivariable models examining percentage change in systolic and diastolic BP, male gender was significantly associated with a change in systolic BP. CONCLUSIONS: In hospitalized children, IV hydralazine was well tolerated, BP response was variable, and 21 % of the patients achieved a ≥25 % reduction of systolic or diastolic BP. Further studies are needed to compare the safety and efficacy of IV hydralazine to other short-acting antihypertensive agents.