Last Updated: October 25, 2026
A study of a topical liquiritin cream is not evidence that an oral licorice elixir belongs on your face. The plant name may be shared, but the constituent, formulation and route are not interchangeable.
Medical disclaimer: This article is educational, not a diagnosis or individualized melasma treatment plan. Discuss persistent pigmentation and treatment suitability with a qualified dermatologist, particularly during pregnancy or while taking medicines. Do not replace prescribed care, use an oral preparation as a facial treatment, or start licorice supplements for melasma based on this article.
The first distinction: licorice is not one standardized intervention
Whole-root extract, liquiritin, glabridin and glycyrrhizin should not be treated as synonyms for the same clinical preparation. The frequently cited melasma paper by Amer and Metwalli (2000), International Journal of Dermatology, studied a topical liquiritin cream, not every licorice-containing serum and not an oral tincture. PMID: 10809983.
That distinction also matters for safety. Penninkilampi et al. (2017), Journal of Human Hypertension, evaluated chronic ingestion of glycyrrhizic-acid-containing products and found blood-pressure and potassium effects. Oral safety findings should not be automatically assigned to every topical cosmetic, but they directly contradict the idea that all routes of licorice use are harmless because the ingredient is botanical. PMID: 28660884.
Our evidence tiers apply to a specific claim: Tier 1 means multiple randomized human trials supporting that outcome; Tier 2 means limited human clinical evidence; Tier 3 means primarily mechanistic evidence; Tier 4 means the proposed clinical benefit remains unconfirmed in the evidence reviewed. A mechanism comparison is not a clinical superiority trial.
What the liquiritin study actually tested
Tier 2, a small split-face human study: Amer and Metwalli (2000), International Journal of Dermatology, studied 20 women with epidermal melasma. Liquiritin cream was applied to one side of the face and vehicle cream to the other twice daily for four weeks. Participants were advised about sun avoidance and/or sunscreen. The study assessed pigmentation intensity, lesion size and clinical response. PMID: 10809983.
The study provides a reason to investigate that intervention, not a universal dose or response-time rule. It excluded pregnancy-associated melasma, dermal melasma and people receiving hormone replacement therapy. Its small, selected population and short treatment period limit generalization to every pigmentation concern or long-term use. Amer and Metwalli (2000), International Journal of Dermatology, PMID: 10809983.
Tier 4 for transferring those findings to every extract: A study of liquiritin does not establish an effective glabridin concentration for all formulations, equivalence of whole-root preparations or benefit from an oral product. Nor does it establish a universal “gentler than kojic acid” or “better for darker skin” ranking. Those require relevant formulation-matched comparisons. Amer and Metwalli (2000), International Journal of Dermatology, PMID: 10809983.
Mechanism claims do not create a superior treatment
Tier 4 for the proposed three-mechanism retail advantage: Listing enzyme inhibition, inflammatory pathways and melanin-related mechanisms does not demonstrate that a particular licorice product outperforms hydroquinone, azelaic acid, vitamin C or alpha arbutin. The liquiritin-versus-vehicle study did not compare every one of those treatments or a multi-product layering routine. Amer and Metwalli (2000), International Journal of Dermatology, PMID: 10809983.
Likewise, “licorice + tranexamic acid + niacinamide” is not automatically the most comprehensive over-the-counter melasma protocol. A plausible combination needs a study of the relevant formula or regimen, not just several mechanisms described side by side.
Where licorice fits within the broader evidence
Clinical evidence synthesis, not a personal prescription: Sarkar et al. (2023), Indian Dermatology Online Journal, reviewed 174 randomized or controlled clinical trials across melasma treatments, with a search through May 2021. Their review gave strong evidence-based recommendations to established options including hydroquinone, triple-combination creams, sunscreens, kojic acid and azelaic acid. It called for larger studies for several newer options, including topical vitamin C and topical tranexamic acid. Its recommendation grades are the authors' framework, not interchangeable with this article's tiers. PMID: 38099013.
This does not mean one medicine is appropriate for every reader. It means a short botanical study should not displace individualized care supported by a much broader literature. Photoprotection is part of melasma management, not something an antioxidant extract replaces. Sarkar et al. (2023), Indian Dermatology Online Journal, PMID: 38099013.
The product-route mismatch in the earlier recommendation
The Licorice Root Elixir previously linked here lists organic licorice root, organic vodka and water. Its catalog directions primarily describe sublingual use, with separate external directions for feet, scalp or navel. That is not the topical liquiritin cream studied for facial melasma. The earlier facial-treatment recommendation has therefore been removed.
Safety evidence, not an efficacy tier: Penninkilampi et al. (2017), Journal of Human Hypertension, pooled 18 studies involving 337 participants and found that chronic ingestion of glycyrrhizic-acid-containing products was associated with higher blood pressure and lower potassium. This does not establish the dose or risk of the specific elixir, whose glycyrrhizic-acid amount was not established here. It does mean oral licorice should not be casually recommended as a cosmetic brightening workaround. PMID: 28660884.
A practical protocol: verify the preparation before building a routine
- Confirm what is being treated. Not every dark patch is melasma. Seek assessment rather than choosing a treatment solely from a photograph or an ingredient trend.
- Check route and constituent. A topical liquiritin cream, a whole-root cosmetic and an oral elixir are different products. Do not substitute one for another.
- Ask for the actual clinical comparison. Look for the finished formula, concentration, comparator, population and outcome. A biochemical assay is not proof of better patient outcomes.
- Keep sun protection in the plan. Discuss appropriate photoprotection with your clinician; do not count licorice or another brightening serum as sunscreen.
- Avoid a mandatory multi-active stack. Do not add licorice, tranexamic acid, niacinamide, azelaic acid and vitamin C at once simply because each has a different proposed mechanism.
- Separate optional cosmetics from treatment evidence. Our Brightening Vitamin C Face Serum is a non-licorice cosmetic alternative for shopping context, not a product established here to treat melasma. Its retrieved description does not establish the exact vitamin C form, concentration or pH.
For broader context, read our botanical-actives evidence guide, green tea versus vitamin C comparison and nutrient needs versus supplement promises. These are educational resources, not a combined prescription.
Commercial disclosure: Veracil sells the cosmetic below. It is an optional non-licorice shopping alternative, not the liquiritin preparation studied for melasma. Inclusion does not establish product-specific melasma efficacy or endorse use of an oral licorice elixir on the face.
Honest limitations
The study reviewed here does not establish indefinite safety, zero irritation, zero rebound risk or a superior profile to all conventional brighteners. A four-week intervention cannot settle those long-term questions. Amer and Metwalli (2000), International Journal of Dermatology, PMID: 10809983.
Oral licorice risks also cannot be ignored or transferred indiscriminately to topical products. Route, formulation and exposure matter. Penninkilampi et al. (2017), Journal of Human Hypertension, PMID: 28660884.
The calibrated verdict
Preliminary Confirm for a defined topical intervention: Liquiritin has small human melasma research that warrants interest, not universal endorsement of licorice extracts. Amer and Metwalli (2000), International Journal of Dermatology, PMID: 10809983.
Inconclusive: Blanket superiority, indefinite safety, an optimal licorice-based multi-active stack or equivalent benefit from a retail oral elixir. Those are not established by the cited trial or the broader melasma review. Amer and Metwalli (2000), International Journal of Dermatology, PMID: 10809983; Sarkar et al. (2023), Indian Dermatology Online Journal, PMID: 38099013.
The useful buying question is not “Does licorice brighten?” It is “Does this exact preparation have evidence for my diagnosis, and is it appropriate for my route of use?”
The Veracil Research Team
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