Antihypertensive effect of Equisetum arvense L.: a double-blind, randomized efficacy and safety clinical trial

Danilo Maciel Carneiro; Thiago Veiga Jardim; Ymara Cássia Luciana Araújo; Ana Carolina Arantes; Andrea Cristina de Sousa; Weimar Kunz Sebba Barroso; Ana Luiza Lima Sousa; Alessandro de Carvalho Cruz; Luiz Carlos da Cunha; Paulo César Brandão Veiga Jardim

doi:10.1016/j.phymed.2022.153955

Antihypertensive effect of Equisetum arvense L.: a double-blind, randomized efficacy and safety clinical trial

Phytomedicine. 2022 May:99:153955. doi: 10.1016/j.phymed.2022.153955. Epub 2022 Jan 26.

Affiliations

¹ Hypertension League, School of Medicine, Federal University of Goiás (UFG), Goiânia, Goiás, Brazil; Reference Center in Integrative and Complementary Medicine of the State Health Department of Goiás, Goiânia, Goiás, Brazil.
² Hypertension League, School of Medicine, Federal University of Goiás (UFG), Goiânia, Goiás, Brazil.
³ NEPET-UFG - Nucleus of Toxicopharmacological Studies and Research, School of Pharmacy, Federal University of Goiás, Goiânia, Goiás, Brazil. Electronic address: alesscruz@yahoo.com.br.
⁴ NEPET-UFG - Nucleus of Toxicopharmacological Studies and Research, School of Pharmacy, Federal University of Goiás, Goiânia, Goiás, Brazil.
⁵ Hypertension League, School of Medicine, Federal University of Goiás (UFG), Goiânia, Goiás, Brazil; School of Medicine of UFG. FM/HC/UFG Hypertension League. Goiânia, Goiás, Brazil.

PMID: 35168030
DOI: 10.1016/j.phymed.2022.153955

Abstract

Background: Equisetum arvense L. (EA) is a traditional phytomedicine used as a diuretic agent worldwide and regulated strictly by European Medicine Agency (EMA) and Brazilian National Health Surveillance Agency (ANVISA). However, few studies evaluating its efficacy and safety have been published and no clinical trial assessing its antihypertensive effect has been reported to date.

Purpose: To assess antihypertensive effect, safety and tolerability of EA compared to hydrochlorothiazide (HCTZ).

Methods: This is a double-blind randomized clinical trial, allocating 58 systemic arterial hypertension (SAH) stage I patients (both sexes, 25-65 years old) into two groups (EA and HCTZ). All patients underwent biochemical and cardiologic checkup prior to and during interventions. The EA standardized dry extract (900 mg/day) or HCTZ (25 mg/day) were administered for 3 months and follow-up visits were conducted every 30 days. Efficacy established goals were systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) decreases ≥ 10.0 mmHg and/or casual blood pressure (CBP) < 140/90 mmHg.

Results: EA treatment demonstrated a significant antihypertensive effect, promoting a mean decrease of SBP and DBP by 12.6 and 8.1 mmHg, respectively, and resulting a CBP mean of 134.0/84.5 mmHg at the end of intervention on the SAH stage I patients (CBP mean of 148.5/95.7 mmHg). There were no significant statistical differences between EA and HCTZ interventions on blood pressure decrease, and before-after treatments regarding to biochemical tests and signs of acute toxicity, renal, hepatic and hematologic alterations. A slight trend but no significant difference were observed between adverse events from EA (3.58%) and HCTZ (4.68%) groups.

Conclusion: EA standardized dry extract was successfully applied to the SAH stage I patient treatment, decreasing effectively SBP ad DBP values to the reference normal ranges, and demonstrating a well-tolerability profile similar to HCTZ intervention.

Keywords: Equisetum arvense L.; Horsetail (Cavalinha); Hypertension; Medicinal plants; Phytotherapy.