What randomized controlled trials exist comparing aged garlic extract to standard antihypertensive medications?

1. What the randomized trials actually tested

The clearest RCTs in the literature randomized patients to AGE versus placebo while participants were typically already receiving standard antihypertensive therapy or were selected for uncontrolled hypertension on medications: Ried et al. randomized treated but uncontrolled hypertensives to 960 mg AGE versus placebo for 12 weeks and reported an average 10.2 mmHg greater fall in systolic BP in those with baseline SBP ≥140 mmHg ^[1], other trials used dose‑response designs with 12‑week follow‑up ^[2], and the AGE at Heart trial and related RCTs also used 12‑week, placebo‑controlled designs in similar populations ^{[3] [2]}.

2. Notable recent triple‑blind, placebo‑controlled trial

A 2023 randomized, triple‑blind trial of an optimized aged black garlic extract (low‑dose S‑allyl‑cysteine, 0.25 mg/day SAC) randomized grade I hypertensive subjects on drug therapy to AGE or placebo for 12 weeks and reported extra‑significant reductions in office and home BP, though effects on endothelial markers were not observed ^{[4] [8]}, reinforcing that contemporary RCTs continue to test AGE as an adjunct rather than as a direct substitute for guideline antihypertensives ^[4].

3. How the findings have been interpreted vs standard drugs

Multiple narrative reviews and meta‑analyses note that the magnitude of BP reduction in some AGE trials is “similar” to that achieved by first‑line antihypertensive agents at 12 weeks, a statement most sources trace to comparisons of effect size rather than head‑to‑head randomization, and meta‑analyses stress heterogeneity across trials, formulations, doses and baseline BP levels ^{[9] [7] [10]}. Systematic reviews conclude AGE may be beneficial—especially at higher doses (>1200 mg/day in one meta‑analysis)—but stop short of saying AGE has been proven equivalent to conventional drugs because the RCT evidence lacks direct randomized comparisons ^{[5] [6]}.

4. Safety and tolerability reported in RCTs

Across the randomized AGE trials, adverse events were generally mild and primarily gastrointestinal complaints or halitosis, with tolerability rated high in several trials; some meta‑analyses report a small increase in minor adverse events in garlic groups but no major safety signals in the AGE RCTs summarized ^{[1] [3] [11]}. Specific drug‑interaction data are limited in these RCTs; trialists typically kept participants on stable antihypertensive regimens rather than substituting AGE for medication, which limits conclusions about safety when used as monotherapy ^{[3] [11]}.

5. Critical gap: no robust randomized head‑to‑head trials identified

The systematic reviews and the RCTs cited repeatedly emphasize that trials compared AGE to placebo as adjunctive therapy and that heterogeneity of preparations, dosing and populations prevents declaring equivalence with standard drug classes; within the provided sources there is no clear randomized controlled trial that enrolls hypertensive patients and directly randomizes them to AGE monotherapy versus a defined standard antihypertensive medication in a head‑to‑head design ^{[5] [6] [7]}. Therefore claims that AGE is “equivalent” to antihypertensive drugs rest on indirect effect‑size comparisons and meta‑analytic synthesis, not on randomized direct comparisons ^{[9] [10]}.

Bottom line

Randomized evidence shows aged garlic extract can reduce blood pressure versus placebo in patients with uncontrolled or grade I hypertension—mostly when given as an adjunct to existing medication—but the literature as presented does not include randomized head‑to‑head trials that compare AGE alone directly against standard antihypertensive drug classes; systematic reviews call for well‑designed trials to test AGE versus active antihypertensive comparators and to standardize formulations and dosing before clinical equivalence can be concluded ^{[1] [2] [5] [6]}.