Case reports tie spirulina to autoimmune flares, so vet any supplement first

Key takeaways

• At a University of Pennsylvania clinic, 36 of 286 people with dermatomyositis, about 1 in 8, had used herbs sold to stimulate the immune system, most often spirulina, typically about a year before the disease began¹.
• A 2025 review found five published cases of dermatomyositis or pemphigus that started or flared after spirulina; three of the five got better after stopping it and starting treatment³.
• In seven trials with 842 people, DHEA modestly improved lupus patients’ sense of well-being but did little for disease activity in mild to moderate lupus, and about 20 more people per 100 got acne⁵.
• In an Australian trial in early rheumatoid arthritis, 5.5 grams a day of fish oil’s EPA and DHA lowered the chance that standard three-drug treatment failed, yet a 2022 U.S. guideline conditionally advises against fish oil for rheumatoid arthritis outcomes⁸¹¹.
• If a flare continues or worsens after you stop a supplement, contact your doctor, and talk with your care team before changing how you take any medicine⁴¹⁵.

Doctors at the University of Pennsylvania keep a database of people with dermatomyositis, an autoimmune disease that inflames the skin and muscles. In 2025 they reported a pattern in it¹.

Of 286 patients, 36 had taken herbs marketed to stimulate the immune system¹. The most common was spirulina, a type of algae that can even turn up in green smoothie drinks¹⁴. The typical gap between first taking the herb and the start of the disease was about a year¹.

That doesn’t prove the herbs caused anything. The study looked back at one clinic’s records, and people’s memories of what they took can be wrong¹. But it fits a worry dermatologists have raised for years. A product designed to rev up the immune system may be a poor match for a disease in which the immune system is already attacking the body².

If you live with lupus, rheumatoid arthritis, multiple sclerosis or Hashimoto’s thyroiditis, the supplement aisle can feel like a place to take back some control. That instinct is worth respecting, and worth arming with facts.

This article sorts the cautions by strength of evidence, from case reports of flares to clashes with the drugs that keep autoimmune disease in check. It also covers the few supplements with real trial support.

“Immune support” is the wrong goal when immunity is the problem

In autoimmune disease, the immune system mistakes the body’s own tissue for a threat. Our article on why the immune system isn’t a volume knob explains that balance.

A 2021 review in the Journal of the American Academy of Dermatology, from the research group of dermatologist Victoria Werth, pulled the concern together². It focused on five products: spirulina, another blue-green algae called Aphanizomenon flos-aquae, chlorella, echinacea and alfalfa².

In lab and animal studies, these herbs switch on immune cells through chemical signals called cytokines². The reviewers called for more lab work to test whether the herbs push on immune pathways that are already overactive in autoimmune disease². Case reports tie such herbs to the onset or flares of lupus, dermatomyositis and blistering diseases such as pemphigus². The reviewers found little to no evidence that the herbs improve skin conditions².

Werth has been blunt about it. “Some patients experience flares or even new onset of disease when they use these herbs,” she said in a 2023 American Academy of Dermatology publication, quoted by The Myositis Association⁴.

These ingredients can hide in ordinary products. The association, a patient group on whose medical advisory board Werth sits, notes that elderberry can turn up in nighttime cold medicine⁴. Read the label on combination products, not just single-herb bottles.

Our articles on echinacea and ashwagandha cover the autoimmune cautions for each of those herbs.

What the case reports show, and what they can’t

The most direct evidence is a small stack of patient stories. In 2025, two researchers searched the medical literature for cases of autoimmune disease linked to spirulina³. They found five patients in four published reports³:

• Three had dermatomyositis and two had pemphigus, a blistering skin disease.
• Four were women, and ages ranged from 45 to 82.
• Symptoms began anywhere from a day or two to a year after starting spirulina.
• All stopped the spirulina and received steroid treatment. Three of the five improved or were cured; the reports didn’t describe the outcome for the other two.

The authors stressed that five cases show an association, not cause and effect, and called for more study³.

The Penn database added a twist. Herb users were less likely than other patients to carry the autoantibodies typical of dermatomyositis: 22% versus 51% for the disease-specific type¹. Skin disease activity didn’t differ¹. The authors suggested the herbs might trigger disease through a different route, and they urged doctors to ask about herbal use when diagnosing and managing the disease¹.

Most of this evidence comes from autoimmune skin and muscle disease²³. In what we reviewed, the concern for other autoimmune conditions rests more on lab findings than on human reports.

There’s good news in the case reports, too. The Myositis Association says symptoms generally ease when the product is stopped⁴. If a flare continues or gets worse after you stop, contact your doctor⁴.

Supplements that can collide with your medicines

Here, the worry is how a supplement might change the medicines that keep an overactive immune system in check, or add risks of its own.

Turmeric and tacrolimus. Tacrolimus is an immune-suppressing drug taken after organ transplants¹³. In 2017, a drug-safety digest called Reactions Weekly summarized a case of kidney toxicity blamed on turmeric taken with tacrolimus¹⁴.

A later case pointed the other way. A team writing in the European Journal of Hospital Pharmacy monitored a kidney transplant patient of about 70 who took 10 grams of turmeric a day for four days, then the same amount of curry, then ginger. Tacrolimus levels didn’t change¹³.

Lab studies do suggest spices can interact with the drug, the authors noted. For patients who eat these spices often, they called a monitored test, agreed on with the care team, a reasonable step¹³.

Two single cases can’t settle the question. If you take tacrolimus and want to use turmeric beyond a cooking amount, tell your transplant or rheumatology team first¹³.

Hidden drugs. The National Center for Complementary and Integrative Health (NCCIH) notes that the FDA has warned consumers about supplements sold for arthritis pain that secretly contain prescription drugs¹⁰. Our guide to supplement seals explains what testing programs such as USP and NSF do and don’t check.

Fish oil. Ask your provider before you start fish oil if you take a drug that changes how your blood clots, or if fish or shellfish give you allergic reactions, NCCIH advises¹⁰.

Probiotics. These live microbes are generally safe in healthy people. In people with serious underlying illness, though, NCCIH says they’ve been tied to dangerous infections¹⁰. Our article on probiotics covers documented hospital cases.

Thunder god vine. This herb may ease some arthritis symptoms. NCCIH warns it can thin bones and cause male infertility, can poison people when the extract is made incorrectly, and may do more harm than good¹⁰.

Our articles on St. John’s wort and on grapefruit and herbs cover two well-documented interaction stories involving anti-rejection drugs.

DHEA and lupus: a hormone that came close to FDA approval

DHEA, short for dehydroepiandrosterone, is a hormone the body makes naturally. Lupus patients often run low on it, and researchers hoped a pill might calm the disease and cut the need for steroid medicines⁵.

A California company, Genelabs, spent years trying to win approval for prasterone, a synthetic form of DHEA⁶⁷. The record shows how hard lupus is to study:

• April 2001. An FDA advisory committee on arthritis discussed the data without taking a vote, and a not-approvable letter followed⁶.
• 2002. The FDA issued an “approvable” letter for preventing bone loss in women with lupus taking low-dose steroids, if another trial confirmed it. The bone data came from a small subgroup, 37 women who took the study drug for a full year, within a 381-woman trial⁶.
• 2004. The confirming trial missed its bone-density goal. A separate trial of 155 patients in Taiwan also showed no clear bone gain⁷.
• January 2006. The FDA said another major trial would be needed. The company said it couldn’t fund one without a partner⁷.

We found no record that the drug was ever approved for lupus.

A 2007 Cochrane review included seven trials with 842 people⁵. DHEA likely did little or nothing for disease activity in mild to moderate lupus⁵. It slightly improved well-being, by about 12 points on a 100-point scale⁵.

The trade-off was acne: about 20 more people out of 100 got it on DHEA⁵. Unwanted hair growth and menstrual changes are possible, and no trial lasted longer than a year, so long-term safety is unknown⁵. The review’s searches ended in 2006, so newer studies aren’t included.

Fish oil in rheumatoid arthritis: a promising trial and a skeptical guideline

In an Australian trial published in 2015, people who had had rheumatoid arthritis (RA) for less than a year and hadn’t yet taken RA drugs were randomly assigned to high- or low-dose fish oil⁸. The high dose delivered 5.5 grams a day of EPA plus DHA, the omega-3 fats in fish. The comparison group got 0.4 grams, a small dose used so no one could tell which group they were in⁸.

Everyone also took three standard RA drugs: methotrexate, sulfasalazine and hydroxychloroquine⁸. In the high-dose group, the three-drug treatment was about one-quarter as likely to fail⁸. People on the high dose were also more likely to reach remission, and side effects and methotrexate doses didn’t differ⁸.

An early report of the trial at a 2012 meeting gave counts, defining failure as needing a fourth drug, leflunomide. The three-drug plan failed in 9 of 75 people on the high dose and 16 of 46 on the low dose⁹. By our math, that’s about 12% versus 35%, or roughly 23 fewer failures per 100 people. One investigator disclosed a tie to a company, Melrose Laboratories, and the pages we read didn’t say who funded the trial⁹.

NCCIH points to a 2017 review of 22 studies with 956 participants that found fish oil eased RA pain¹⁰.

Yet the American College of Rheumatology (ACR) went the other way. Its 2022 guideline on diet and integrative care made a conditional recommendation against several supplements, including vitamin D, fish oil and glucosamine, judged on whether they improve RA itself¹¹. It conditionally favored a Mediterranean-style diet over no particular diet¹¹¹².

How can both be true? The guideline weighed only RA-specific outcomes¹¹. Its panel added that supplements may have other health uses, which makes shared decisions between patients and clinicians important¹². A single positive trial at a high dose is a lead, not a settled answer.

Our vitamin D article covers that vitamin’s autoimmune trial. NCCIH adds that oils with gamma-linolenic acid, such as evening primrose, borage and black currant oil, may help some RA symptoms, though each has only a few studies, and some borage products contain liver-damaging compounds¹⁰.

Diet, gluten and pregnancy

The autoimmune protocol diet has its own article, which reviews its small studies. Celiac disease, where gluten is the known trigger, has its own guide in this library. For RA, the ACR conditionally favored a Mediterranean-style pattern¹².

Pregnancy changes the picture. MotherToBaby, a service of a nonprofit group of pregnancy-exposure specialists, says about half of women with RA feel better during pregnancy, and about half may flare in the months after delivery¹⁵. It advises talking with your providers before changing how you take any medicine¹⁵. You can call 866-626-6847 or text 855-999-3525 with questions about medicines and other exposures in pregnancy¹⁵.

The autoimmune supplement check

Wanting to care for your body with food and plants fits a long tradition. Choosing carefully is part of that tradition, too. Use this table to sort a product before you buy it.

Supplement or product	The concern	How strong the concern is	What to do
Spirulina, chlorella, blue-green algae, including in green drinks	Onset or flares of dermatomyositis, pemphigus and lupus	Case reports, one clinic study and lab work; cause not proven123	Skip if you have autoimmune skin or muscle disease; tell your doctor if you’ve used it14
Echinacea, alfalfa, elderberry, ashwagandha	Same immune-stimulating concern	Lab studies and case reports for some; on the Penn study’s herb list12	Ask before using; check cold remedies and blends4
Turmeric in supplement doses with tacrolimus	Changed drug levels	Two cases with opposite results1314	Tell your transplant or rheumatology team; ask about monitoring13
Fish oil	Possible clash with blood-clotting medicines; fish allergy	Federal caution10	Check with your provider first10
Probiotics	Infection in people with serious illness	Documented in very sick patients10	Ask if you take strong immune-suppressing drugs10
Thunder god vine	Bone loss, male infertility, poisoning	Documented serious harm10	Don’t self-treat with it10
“Arthritis” or pain blends	Hidden prescription drugs	FDA warnings10	Be wary of drug-like promises; show the bottle to your pharmacist10
DHEA	Acne, hair growth, unknown long-term safety	Seven trials5	Discuss with your rheumatologist5

Five questions before adding any supplement

1. Does it promise to “boost” or “stimulate” immunity? In autoimmune disease, that’s the effect researchers worry about²⁴.
2. Was it tested in people with my condition, in this form and dose? The positive fish oil trial used 5.5 grams of EPA plus DHA a day, alongside standard drugs⁸.
3. Could it change my drug levels or add to a side effect? Ask your pharmacist, especially if you take tacrolimus or a blood thinner¹⁰¹³.
4. Am I pregnant or planning to be? MotherToBaby can help¹⁵.
5. What’s my stop plan? Write down when you started. If a flare continues after you stop, call your doctor⁴.

Bring the actual bottles to appointments. NCCIH advises talking with your provider before adding any supplement and never using one in place of prescribed treatment¹⁰.

How strong is the evidence?

Claim	Rating	Why
Immune-stimulating herbs are safe with autoimmune skin or muscle disease	Evidence says no, or unsafe	Case reports of onset and flares, though cause isn’t proven123
DHEA improves lupus well-being in the short term	Promising but early	Seven trials; modest effect; acne common5
DHEA calms lupus disease activity	Evidence says no, or unsafe	Little or no difference in mild to moderate disease5
Prasterone protects bone in lupus	Evidence says no, or unsafe	Confirming trials missed their goals7
High-dose fish oil helps early RA alongside standard drugs	Promising but early	One positive trial and a favorable pain review, but the ACR conditionally advises against it81011
GLA oils ease RA symptoms	Promising but early	Few studies per oil10
Thunder god vine for RA	Evidence says no, or unsafe	Some benefit, serious harms10
Probiotics for RA	Not enough evidence	NCCIH says no conclusions can be drawn yet10
Turmeric changes tacrolimus levels	Not enough evidence	Two single cases disagree1314
Mediterranean-style diet for RA	Promising but early	Conditional ACR recommendation1112

Questions readers ask

The bottom line

When the immune system is already overactive, “immune boosting” is the wrong promise. The cautions are strongest for spirulina and related herbs in autoimmune skin and muscle disease, where case reports and a clinic study raise a real flag, though not proof.

A few supplements have earned a second look: high-dose fish oil in early RA and DHEA for lupus well-being. Even those come with trade-offs and a guideline that isn’t convinced. Bring every bottle to your care team, ask the five questions and never trade a proven medicine for a supplement.

Related reading

• Your immune system works more like a team than a volume knob, and some habits help it
• Vitamin D barely touched colds in big trials, but its autoimmune results were more intriguing
• St. John’s wort may ease mild depression, but it can undercut your other medicines
• What happens when you don’t tell your doctor about supplements
• Popular elimination diets promise to find your triggers, but few have been tested

Sources

1. McCrear S. “Herbal Use Linked to Lower Autoantibodies in Dermatomyositis” (on Yang X, On A, Chambers S, et al., research letter, JAMA Dermatology, published online November 5, 2025). AJMC, November 19, 2025. ajmc.com
2. Bax CE, Chakka S, Concha JSS, Zeidi M, Werth VP. “The Effects of Immunostimulatory Herbal Supplements on Autoimmune Skin Diseases.” Journal of the American Academy of Dermatology, 2021;84(4):1051-1058 (abstract). em-consulte.com
3. de Carvalho JF, Martinez ATA. “Spirulina Ingestion and Autoimmune Disease Onset or Flare.” Advances in Rheumatology, 2025;65:15. biomedcentral-advancesinrheumatology.publicaciones.saludcastillayleon.es
4. Kobert L. “Immune Boosting Supplements Can Make Autoimmunity Worse.” The Myositis Association, April 8, 2024. 300.myositis.org
5. Crosbie D, Black C, McIntyre L, Royle PL, Thomas S. “Dehydroepiandrosterone for Systemic Lupus Erythematosus.” Cochrane Database of Systematic Reviews, 2007, Issue 4 (abstract and plain language summary). cochranelibrary.com
6. BioWorld. Report on Genelabs’ “approvable” letter for Prestara (prasterone) in lupus. September 3, 2002. bioworld.com
7. Boggs J. “Genelabs’ Prestara Headed for New Phase III Lupus Trial.” BioWorld, January 17, 2006. bioworld.com
8. Proudman SM, James MJ, Spargo LD, et al. “Fish Oil in Recent Onset Rheumatoid Arthritis: A Randomised, Double-Blind Controlled Trial Within Algorithm-Based Drug Use.” Annals of the Rheumatic Diseases, 2015;74(1):89-95 (abstract). pubmed.ncbi.nlm.nih.gov
9. Proudman SM, et al. “Fish Oil in Rheumatoid Arthritis: A Randomised, Double-Blind Trial Comparing High Dose With Low Dose” (meeting abstract). ACR/ARHP Annual Meeting, 2012. acrabstracts.org
10. National Center for Complementary and Integrative Health. “Rheumatoid Arthritis: In Depth.” NCCIH, last updated January 2019. nccih.nih.gov
11. Hickman RJ. “Guideline for Integrative RA Interventions Released” (on England BR, Smith BJ, Baker NA, et al., 2022 American College of Rheumatology guideline). The Rheumatologist, August 3, 2023. the-rheumatologist.org
12. American College of Rheumatology. “New Guideline Introduces Recommendations for Integrative Approach to RA Treatment.” Press release, November 7, 2022. rheumatology.org
13. Boissiere C, Francois E, Vabret E, Le Daré B, Bacle A. “Spice-Drug Interactions: A Case Report on the Use of Turmeric, Curry and Ginger in a Renal Transplant Patient on Tacrolimus.” European Journal of Hospital Pharmacy, 31(1):68 (abstract). pubmed.ncbi.nlm.nih.gov
14. “Tacrolimus/Turmeric Interaction: Nephrotoxicity: Case Report.” Reactions Weekly, issue 1638, February 11, 2017 (ProQuest record). proquest.com
15. MotherToBaby (Organization of Teratology Information Specialists). “Rheumatoid Arthritis” fact sheet. July 1, 2026. mothertobaby.org