Rosmarinic Acid

Snapshot

Indications	Contraindications
Alzheimer's neuropsychiatric symptoms¹ Glycemic support² Skin barrier function (topical)^{3, 4}	Pregnancy or nursing⁵ Soy allergy (some products)⁵

Rosmarinic acid is a phenolic ester found in more than 160 plant species, especially the mint family (Lamiaceae)⁶. Anti-inflammatory and antioxidant activity drives supplementation⁶. Uses that follow include cognitive aging and neuropsychiatric symptoms in mild Alzheimer's disease, plus glycemic support, studied mainly in preclinical work. Typical users are older adults with subjective or mild cognitive impairment, taking a lemon balm extract standardized to rosmarinic acid⁷.

Human research is limited to about nine small trials, mostly in cognition and Alzheimer's disease, pharmacokinetics, seasonal allergy, and knee osteoarthritis. A 2023 randomized trial in older adults without dementia found no difference in cognitive measures, with a signal only in participants without hypertension⁷. A 2020 trial in mild Alzheimer's disease found no cognitive difference but better neuropsychiatric symptom scores¹. In animal behavioral tests, a 2022 study of a Salvia limbata extract found sedative-hypnotic and anxiolytic effects that flumazenil reversed; no human trial has tested it. Products listing rosmarinic acid are mostly capsules and softgels, often combined with other botanicals; see Form comparison.

Some product labels ask for a health care professional's advice before use alongside medications⁵.

Last updated October 17, 2026. Read how we make monographs.

In the full monograph

30 sources, 22 studies

When to useThe situations practitioners use it for, each with the reason and the study behind it.
SafetyWho should avoid it, who needs extra care, and the side effects reported in studies.
InteractionsThe medicines and supplements it interacts with, the effect of each, and what labeling says to watch.
Protocol notesThe doses used in studies, how and when they were taken, and how the forms on the market compare.
How it worksWhat it is and how it works in the body, in plain terms.
Published studiesThe studies behind each use, popular claims checked against them, and trials still under way.
Word of mouthWhat patients and practitioners report online, kept separate from the clinical evidence.
Clinical perspectiveA closing read of where the evidence is solid, where it is thin, and what has not been studied.

Snapshot

In the full monograph

Sources