If you are looking at probiotics for your skin, Lactobacillus rhamnosus deserves a close look. A placebo-controlled trial of L. rhamnosus alone, and one of L. rhamnosus with spirulina, both found more improvement than placebo.[1][2]
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From Anirva, the maker of ClearDerm with Probiotics. This article is general information, not medical advice. 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.
- L. rhamnosus has its own acne trial. In an adult pilot, more people improved than on placebo.[1]
- A second trial combined it with spirulina. Acne improved in 50% of people on the combination and 29% on placebo.[2]
- Its main thread is inflammation. In a lab study of the strain 4B15, inflammation signals fell in immune cells.[4]
- ClearDerm includes it in a six-species blend of 6 billion CFU a day.[8]
Facts at a glance
| Fact | Detail |
|---|---|
| Ingredient | Lactobacillus rhamnosus, one of six probiotic species in ClearDerm |
| Amount in ClearDerm | Part of a 6 billion CFU blend a day; the label gives no amount per species |
| Amount in the acne trials | 3 billion CFU a day (pilot trial); not given in the second trial's abstract |
| Kinds of evidence | Two placebo-controlled acne trials by mouth; lab studies; a 2026 meta-analysis of Lactobacillus products (no significant effect) |
| Human acne trials described here | 2, both against placebo |
| Last reviewed | [DATE] |
What is Lactobacillus rhamnosus?
L. rhamnosus, also called Lacticaseibacillus rhamnosus, is a lactic acid bacterium.[2] Strains carry code names, such as SP1 or GG.[1][5] Effects can differ between strains.[7]
How may L. rhamnosus calm inflammation?
Acne is an inflammatory skin condition, and microbes may play a part.[6]
- In immune cells. In a lab study, the strain 4B15 lowered TNF-α, IL-6 and IL-1β in mouse immune cells. It also lowered IL-10, a calming signal, so the results were mixed.[4]
- In people. In 42 placebo trials in adults (not acne trials), probiotics as a group lowered CRP, TNF-α and IL-6.[3]
- In skin cells. In the lab, the strain GG protected human skin cells from Staphylococcus aureus: 57% survived, against about 25% without it.[5] Neither lab result was tested in people.
The research is still growing on how this carries over to skin.
Does L. rhamnosus help acne? What the trials show
A pilot trial in adults (2016)
Twenty adults with acne, average age 34, took L. rhamnosus SP1 (3 billion CFU a day) or a placebo for 12 weeks.[1]
In the probiotic group, skin IGF1 gene activity fell by 32% from the start; IGF1 is part of insulin signalling, which is linked to acne. Placebo showed no change.[1]
Doctors rated more of the probiotic group as improved, though with 10 people per group the estimate is uncertain.[1]
A larger trial with spirulina (2024)
People aged 12 to 30 took L. rhamnosus CECT 30031 with spirulina, or a placebo, for 12 weeks; 74 completed it.[2]
Acne improved in 20 of 40 people (50%) on the probiotic capsule and 10 of 34 (29%) on placebo. Side effects were similar in both groups.[2]
Study summary
| Study | What was taken | People and length | Result |
|---|---|---|---|
| Fabbrocini 2016 | L. rhamnosus SP1; 3 billion CFU | 20 adults; 12 weeks; vs placebo | IGF1 −32% from the start; more rated improved |
| Eguren 2024 | L. rhamnosus CECT 30031 with spirulina | 74 analyzed, aged 12–30; 12 weeks; vs placebo | Improved: 50% vs 29% |
How much is in ClearDerm?
ClearDerm provides 6 billion CFU a day from six species, including L. rhamnosus; the label gives no amount per species or strain name.[8] The pilot trial used 3 billion CFU a day of one strain.[1]
Is L. rhamnosus safe?
The NIH notes a greater risk of harm in people with severe illness or a weakened immune system.[7]
L. rhamnosus is one part of ClearDerm
ClearDerm with Probiotics is a daily two-capsule skin supplement with 22 ingredients: vitamins, minerals, plant extracts, an enzyme and six probiotic strains. They were chosen to promote clear skin, support a clear complexion and support the gut–skin connection. L. rhamnosus is one of them.[8]
ClearDerm has not been clinically tested as a finished product. When you take it, you are not relying on one ingredient alone.
ClearDerm is made in Phoenix, Arizona, in a cGMP-certified facility. Every ingredient is listed on the label, and the probiotic blend is given as one total.[8]
Probiotics have a long history of apparently safe use, especially in healthy people.[7] In the acne trials, side effects were similar to placebo.[1][2] A few points help you use it well: the acne trials ran 12 weeks[1][2]; take ClearDerm with food and water, as the directions say[8]; and if you are pregnant or nursing, have a weakened immune system or a serious illness, or take any medicine, ask your doctor or pharmacist before you start.[7][8]
22 ingredients, including L. rhamnosus
ClearDerm with Probiotics is a daily two-capsule supplement that pairs a six-species probiotic blend with other vitamins, minerals and plant extracts chosen to support clear skin. Every ingredient is listed on the label.
See ClearDermIf you are deciding
Here is the case in brief. In a pilot trial, L. rhamnosus lowered a skin gene linked to acne, and more people improved.[1] With spirulina, acne improved in 50% of people, against 29% on placebo.[2] The evidence is promising but small.[9] ClearDerm includes L. rhamnosus.[8]
The short version
L. rhamnosus alone, and with spirulina, each did better than placebo in an acne trial. ClearDerm includes it.
Frequently asked questions
Is Lactobacillus rhamnosus good for acne?
What do lab studies show for L. rhamnosus?
How much L. rhamnosus was used in studies?
The pilot trial used 3 billion CFU a day.[1]
Is L. rhamnosus safe?
Is L. rhamnosus in ClearDerm?
Yes. It is one of six species in ClearDerm's probiotic blend, 6 billion CFU a day in total.[8]
References
- Fabbrocini G, Bertona M, Picazo Ó, Pareja-Galeano H, Monfrecola G, Emanuele E. Supplementation with Lactobacillus rhamnosus SP1 normalises skin expression of genes implicated in insulin signalling and improves adult acne. Benef Microbes. 2016;7(5):625-630. doi:10.3920/BM2016.0089. PMID: 27596801.
- Eguren C, Navarro-Blasco A, Corral-Forteza M, Reolid-Pérez A, Setó-Torrent N, García-Navarro A, et al. A randomized clinical trial to evaluate the efficacy of an oral probiotic in acne vulgaris. Acta Derm Venereol. 2024;104:adv33206. doi:10.2340/actadv.v104.33206. PMID: 38751177.
- Milajerdi A, Mousavi SM, Sadeghi A, Salari-Moghaddam A, Parohan M, Larijani B, et al. The effect of probiotics on inflammatory biomarkers: a meta-analysis of randomized clinical trials. Eur J Nutr. 2020;59(2):633-649. doi:10.1007/s00394-019-01931-8. PMID: 30854594.
- Oh NS, Joung JY, Lee JY, Kim Y. Probiotic and anti-inflammatory potential of Lactobacillus rhamnosus 4B15 and Lactobacillus gasseri 4M13 isolated from infant feces. PLoS One. 2018;13(2):e0192021. doi:10.1371/journal.pone.0192021.
- Mohammedsaeed W, McBain AJ, Cruickshank SM, O'Neill CA. Lactobacillus rhamnosus GG inhibits the toxic effects of Staphylococcus aureus on epidermal keratinocytes. Appl Environ Microbiol. 2014;80(18):5773-5781. doi:10.1128/AEM.00861-14.
- Lee YB, Byun EJ, Kim HS. Potential role of the microbiome in acne: a comprehensive review. J Clin Med. 2019;8(7):987. doi:10.3390/jcm8070987. PMID: 31284694.
- National Center for Complementary and Integrative Health. Probiotics: usefulness and safety. Last updated August 2019. https://www.nccih.nih.gov/health/probiotics-usefulness-and-safety (accessed October 9, 2026).
- Anirva. ClearDerm with Probiotics Supplement Facts label and product page. https://anirva.com/pages/clear-derm-with-probiotics (accessed October 9, 2026).
- Abedin ZU, Shah A, Mazhar S, Khan SM, Aamir AB, Yousaf S, et al. Lactobacillus-based microbiome therapy for acne vulgaris: a GRADE systematic review and meta-analysis of randomized controlled trials. J Cosmet Dermatol. 2026;25(3):e70792. doi:10.1111/jocd.70792. PMID: 41853869.
