Research review
Does milk thistle help with acne, eczema, or rosacea? What the research does and doesn't show
Human trials on milk thistle and skin tested topical creams and serums, not the oral capsules most people mean by a milk thistle supplement, and several combined silymarin with a second ingredient so its own effect isn't isolated. No trial has tested any form for hormonal acne specifically.
The evidence doesn't support milk thistle capsules — the oral form most people mean by "taking milk thistle" — as a treatment for acne, eczema or rosacea. The human trials that exist tested topical creams and serums, mostly small and short, and several combined silymarin (milk thistle's active complex) with another ingredient, so silymarin's own contribution isn't clear.
What the evidence doesn't support
It doesn't support oral milk thistle — the capsules, tablets and standardized extracts covered elsewhere on this site — for any skin condition; no trial has tested the oral form on acne, eczema or rosacea. It also doesn't support milk thistle, in any form, as a treatment for hormonal acne specifically: none of the trials below separated hormonal acne from acne vulgaris generally. And it doesn't support "before and after" claims made in skincare marketing, which aren't controlled research.
What the trials found
Acne
A 2023 open-label pilot study gave 22 Korean adults with mild-to-moderate acne a 0.5% silymarin antioxidant serum to apply twice daily for four weeks, on top of whatever acne treatment they were already using. Acne severity scores and lesion counts fell significantly; sebum output and skin pigmentation also improved, though only the pigmentation change reached statistical significance. There was no placebo group, so how much of the improvement came from the serum versus the existing treatment or time alone can't be separated out.
A 2024 industry-authored report described two similar studies of a commercial silymarin antioxidant serum: a 12-week, 56-person study in Brazil (45% fewer inflammatory lesions, 43% fewer non-inflammatory lesions, no placebo arm described) and a US/German study where 40 people already on prescription acne treatment added the serum and saw less facial redness, dryness and scaling. Neither study, as reported, included a placebo comparison.
A 2024 split-face trial in 30 people with mild-to-moderate acne applied a 1.4% silymarin cream to one side of the face twice daily for three months, while the other side received salicylic acid peels every two weeks. Acne severity fell significantly on both sides of the face over the three months, and no side effects were reported for the cream.
One trial tested the oral form: 60 people with acne vulgaris were split three ways — oral silymarin, the antibiotic doxycycline, or both — and followed for several months using standard acne-severity scales. We don't report the trial's comparative result here, because comparing a supplement to a prescription antibiotic isn't a comparison this page makes; what's worth noting is that this is the only trial we found testing oral silymarin, the form actually sold as a milk thistle supplement, against any acne outcome.
Eczema
A 2022 trial randomized 40 people with mild-to-moderate eczema to a prescription topical steroid or an herbal cream combining silymarin with a second herb, Fumaria officinalis, for two weeks, tracked with the SCORAD severity scale. Because the cream combined two herbs, it doesn't isolate what silymarin itself did, and we don't report the head-to-head result of a supplement tested against a prescription steroid. Separately, a 2008 study in mice bred to develop eczema-like skin changes found that topical silymarin reduced those changes — a lab finding in an animal model, not evidence about a cream or capsule used by a person.
Rosacea
The one placebo-controlled human trial we found combined silymarin with methylsulfonylmethane (MSM), not silymarin alone. In this 2008 study, 46 people with early-to-moderate rosacea used the combination cream or a placebo cream for one month; the treated group showed a statistically significant improvement (p<0.001) in redness, papules, itching and skin hydration measured by instrument. Because MSM was part of the formula, this trial doesn't tell us what silymarin alone would do for rosacea.
| Condition | What's been tested | Design | Isolates silymarin? |
|---|---|---|---|
| Acne | Topical serum/cream (0.5%–1.4%); oral, in one trial | Mostly open-label or split-face, small, short | Yes, in most |
| Eczema | Cream combined with a second herb | 2 weeks, vs a prescription steroid | No |
| Rosacea | Cream combined with MSM | 1 month, placebo-controlled | No |
Questions people ask
Does milk thistle help with acne?
Small trials of topical silymarin serums and creams — not the capsules sold as a milk thistle supplement — reported less acne severity over several weeks to months. Most had no placebo group, so it's hard to know how much of the change the serum itself caused. Only one trial tested the oral capsule form, and it used a prescription antibiotic as a comparison arm rather than a placebo.
Can milk thistle help hormonal acne?
None of the trials distinguished hormonal acne from acne vulgaris generally, so there's no research specifically on that subtype.
Does milk thistle help with eczema?
The one human trial tested a cream combining silymarin with a second herb against a prescription steroid, which means it doesn't show what silymarin alone does for eczema. No trial has tested oral milk thistle capsules for eczema.
Is milk thistle good for rosacea?
The one placebo-controlled trial combined silymarin with MSM and found a significant improvement in redness and other measures versus placebo — but because it's a two-ingredient formula, it doesn't isolate silymarin's own effect, and no trial has tested silymarin alone for rosacea.
What does "milk thistle acne before and after" usually show?
Those images come from skincare marketing, not the controlled trials above. A before-and-after photo doesn't control for other products used, time, lighting or camera settings, so it isn't evidence of what an ingredient did on its own.
When to talk to a doctor
Acne, eczema and rosacea are diagnosable skin conditions with established prescription and over-the-counter treatments; a dermatologist can evaluate persistent or worsening symptoms. Milk thistle, in any form, is not a treatment for any of these conditions, and nothing in the research above supports using it as a substitute for a dermatologist's evaluation or a prescribed treatment. If a skin condition is painful, spreading or affecting quality of life, that's worth raising with a doctor rather than treating with a supplement search.
Related reading: milk thistle oil and topical products, milk thistle: what the research does and doesn't show, and milk thistle side effects.
Sources
- Efficacy and safety of silymarin containing antioxidant serum as an adjuvant treatment of mild-to-moderate acne vulgaris: A prospective, open-label pilot study A small, open-label, no-placebo study found a 0.5% silymarin serum used alongside existing acne treatment for 4 weeks was linked to less acne severity in 22 people, but with no placebo group to compare against.
- A Silymarin Antioxidant Serum Improves Facial Acne Alone and as Part of a Treatment Regimen Two industry-reported studies (56 and 40 people) found a silymarin antioxidant serum was linked to fewer acne lesions and less redness/dryness/scaling over 12 weeks, with no placebo group described.
- Topical Silymarin Cream as a Novel Therapy Versus Salicylic Acid Peels in Acne Vulgaris: A Split-Face Clinical Trial A 3-month split-face trial in 30 people found acne severity fell significantly on both the silymarin-cream side and the salicylic-acid-peel side of the face, with no side effects reported for the cream.
- Efficacy and safety of oral silymarin in comparison with oral doxycycline and their combination therapy in the treatment of acne vulgaris One trial tested oral silymarin capsules against the antibiotic doxycycline for acne in 60 people — the only trial found on the oral supplement form, though we don't report its comparative result here.
- Effect of herbal cream containing Fumaria officinalis and silymarin for treatment of eczema: A randomized double-blind controlled clinical trial A 2-week trial in 40 people with mild-to-moderate eczema tested a cream combining silymarin with a second herb against a prescription topical steroid; because it's a two-herb formula compared with a prescription drug, it doesn't show what silymarin alone does for eczema.
- Inhibition of atopic dermatitis by topical application of silymarin in NC/Nga mice A mouse study (not in humans) found topical silymarin reduced eczema-like skin changes in mice bred to develop them — an animal finding, not evidence about a human cream or capsule.
- Combined effects of silymarin and methylsulfonylmethane in the management of rosacea: clinical and instrumental evaluation A month-long, placebo-controlled trial in 46 people with rosacea found a cream combining silymarin and MSM significantly improved redness, papules, itching and hydration versus placebo — but because it's a two-ingredient formula, it doesn't show what silymarin alone would do.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.