When Gloria Caballero, 52, started experiencing knee pain four years ago, her sister in Los Angeles suggested a natural remedy that a coworker had sworn by: a supplement called Artri King. Following her advice, Gloria started buying the yellow-and-blue pills in Los Angeles and bringing them up to her home in San Francisco, where she started taking them twice a day, every day.

The change, Caballero said, was dramatic. She could walk without pain again. After long days cleaning houses, she woke up energized. But as time passed, her face started to swell. Bruises appeared all over her body, so many that she started wearing long sleeves to cover them. Amid the stress of juggling multiple gigs to afford San Francisco’s high rent, the house cleaner didn’t think much of her symptoms.

Then, during a routine check-up this May at a community clinic, her nurse practitioner asked about what medicines and supplements she was taking, and she mentioned Artri Ajo King. When he looked up the supplement online, he told her she would have to stop. The pills, it turned out, have been found to contain hidden prescription drugs. They were responsible for her bruises and her swelling, and for other worrying changes she hadn’t yet noticed in her body.  

In San Francisco, a growing number of Latinos who work physically demanding jobs are turning to supplements like Artri Ajo King and related supplements, such as Artri King, AK Forte and Ortiga Ajo Rey to relieve chronic pain. The supplements are marketed as natural remedies for pain relief. But there’s a dark side to the pills that has doctors in the city worried. They contain hidden pharmaceuticals that can lead to serious medical conditions, including liver toxicity and death. Quitting them abruptly can also be very dangerous. And though the Food and Drug Administration (FDA) has asked people to avoid them, the message of their harms doesn’t seem to be getting across to Spanish speaking immigrants, or to the many small businesses in the Mission District that cater to them. 

The supplements’ labels, written fully in Spanish, say the product is made in Mexico, and list ingredients like Vitamin C and collagen. However, FDA laboratory analyses have found they also contain powerful hidden drugs like diclofenac, dexamethasone and methocarbamol, which are used to treat a number of health conditions, but require a doctor’s prescription to avoid severe side effects. 

“The tricky part is, patients actually feel better because the high-dose steroids treat arthritis pain,” said Elizabeth Murphy, chief of the Endocrinology and Metabolism Division at the San Francisco General Hospital. “The problem is, it’s just not a safe treatment for joint pain. And because it’s not a listed ingredient, you don’t even know how much of these steroids is in the medication. You don’t even know which steroid it is.”

San Francisco cases on the rise

Over the past few years, Murphy said she has seen a number of patients in San Francisco with complications linked to Artri Ajo King and its derivatives. 

“It’s unfortunately very common.” she said. “And we’re seeing more and more (cases).”

Sometimes, she said, patients are referred to her because the hidden steroids have disrupted their hormone production, causing them to develop severe osteoporosis and broken bones — Murphy said she’s had patients who had to have both hips replaced. Others gain weight, develop diabetes, or show other symptoms of Cushing’s syndrome, which is typically caused by rare tumors in the adrenal glands, but can also be triggered by steroid use.

In other parts of the country, doctors have also reported cases of Artri Ajo King users who have been hospitalized with bleeding ulcers, adrenal insufficiency, nausea and vomiting. Surgeons at a predominantly Latino-serving hospital in Los Angeles started screening pre-operative patients for Artri Ajo King usage, because it can bring life-threatening complications during surgery. 

Given the risk of severe side effects, Murphy has also been educating fellow S.F. providers to ask about supplements during intake, helping doctors catch the issue before conditions worsen.

Still, though practitioners have been able to catch cases earlier on, she said, use of Artri Ajo King in San Francisco’s Latino community has increased, mirroring medical reports of their rising popularity in the U.S. In the last six months alone, Murphy said she saw three patients with complications derived from Artri Ajo King usage in the city. She suspects there are many more people with symptoms that haven’t been linked to the supplement.

Leiner, the nurse practitioner that treated Caballero, said it’s hard for doctors to identify Artri Ajo King usage because people won’t feel bad taking them until “something major happens,” like an infection that pushes them into shock, or a broken bone that reveals osteoporosis. 

“A lot of the symptoms would be subtle,” said Leiner, who works at the Mission Neighborhood Health Center (MNHC). “I didn’t even make the connection when I first saw my patient [Gloria]. She had bruises on her skin. That’s not unusual for 50-year-old women.”

Caballero’s bruises were caused by thinned skin, a hallmark of Cushing’s syndrome. Blood tests showed her natural cortisol levels neared zero. Another patient of Leiner’s, who had only taken the pills for three months, also showed alarmingly low cortisol levels.

These hormonal imbalances caused by Artri Ajo King also complicate people’s ability to stop taking the supplement safely. Long-term use shuts down the body’s natural production of cortisol, Leiner explained, so people need to contact their medical provider to be successfully weaned off the medication. Depending on how long a patient has been taking the supplements, the process “might take years.” 

“If you bring usage down too quickly, the body is not going to be able to generate its own cortisol in the event of a major injury,” said Leiner. “If these patients were to have had a bad fever or a major car accident, they’d go into shock and they could die.”

Easy to find, easy to buy

After receiving FDA warning letters in 2022, big retailers like Walmart and Amazon issued voluntary recalls, pulling Artri Ajo King and Artri King from their shelves. The supplements are now on the FDA’s “red list” of import alerts and Customs and Border Protection (CBP) has also seized shipments of Artri King at U.S. ports of entry. But in San Francisco stores catering to Latin American, Spanish-speaking consumers, the supplement is still popular and readily accessible.  

On a walk through the Mission District, El Tecolote found 12 small stores, including a Latino pharmacy, that sold Artri King or close derivatives. Most were along two of the neighborhood’s business corridors: Mission Street and 24th Street. Often, the bottle was displayed near low-grade pain medication like Tylenol or next to other supplements advertised as natural remedies. They retailed for $20 to $40 a box. 

El Tecolote bought two boxes at a small grocery store specializing in Latin American products. Inside each box was a QR code to a Google Drive PDF claiming to “authenticate” the product. The outside label instructed consumers to take two pills, three times a day, never mentioning the hidden steroids. In italics, one line read:

“Taking this product is the responsibility of whoever takes it, and whoever recommends it.”

Clerks in several stores said that the supplements were popular among older Latino men and women seeking pain relief, who had heard about it through word-of-mouth recommendations. At the stores, consumers don’t need a prescription to buy the supplement. 

Clerks and managers said they were unaware of the FDA warnings and the impact of the hidden ingredients. They were skeptical of the product’s harm, and said that Artri King was just one of many medications they received in bulk from their suppliers.

One store manager said he gives the supplement to his mother, and takes it himself occasionally. At another store, a clerk said she started using the pills after customers recommended them. She reported selling three to four boxes a day. Sometimes, a single customer buys out the entire stock.

The problem with alternatives 

At Mission Street’s Milagros de México, a large herbal store specializing in Latin American supplements, pharmacy worker Consuelo Hernández said they stopped selling Artri King after the FDA issued warnings. When customers ask for it, she steers them towards the store’s other pain-relief products, including derivatives with similar branding. 

Many health providers, however, warn against taking one of these derivatives, since there’s no guarantee they’re not just a repackaged version of the Artri Ajo King formula.

Because products like Artri Ajo King are marketed as supplements, and not medications, the FDA cannot regulate their ingredients before they hit the market. Rather, the labeling responsibilities fall on the manufacturer. The FDA only steps in to test and recall products after they receive multiple reports of harm.

“There’s no way to distinguish legitimate supplements from illegal supplements,” said Pieter Cohen, an associate professor of Medicine at Harvard Medical School who researches supplement safety. 

Although he regularly recommends vitamins and mineral supplements to his patients, Cohen advises them to avoid ones that claim to offer pain relief, since they often contain “powerful prescription drugs.” Any supplement that provides immediate results, he added, probably contains something beyond legal ingredients. 

“There might be some real misleading advertising going on,” he said.

Getting the message across

Artri Ajo King has no official website, and Mexican doctors have warned that it is made in “hidden laboratories” and is “not regulated at the local level,” with “chameleon-like” industries that are good at evading public health regulations. Though its label says it is made in Mexico, the box doesn’t provide any contact information for the supplement’s supposed manufacturer, listing only an address in a residential neighborhood in Mexico City.

But despite government warnings in multiple countries over Artri King’s hidden ingredients, the supplement remains popular across the U.S. and in Latin America. 

Cohen, who has studied how similar supplements impact Boston’s Brazilian community, said FDA warnings rarely change consumer behavior, particularly among lower-income, immigrant populations who may not know about or understand them.

“I think people should be really concerned,” Cohen said, adding that lack of health insurance in immigrant communities makes it “really common to turn to other solutions.”

Mayra Moreno-Arnaiz, a senior health educator at MNHC, echoed that concern. She said many patients assume the pills are “natural” or similar to traditional remedies passed down in Latino families. In reality, they are factory-made and unregulated.

Moreno-Arnaiz designed flyers warning patients of the risks, now posted in the clinic. But getting the message across has proven to be difficult. Some people don’t trust the medical system and decide to self-medicate their chronic pain. Long wait times for medical appointments might discourage people who do have Medi-Cal from seeking help for less serious conditions. 

There’s also the fact that, as Cohen noted in one of his studies, small stores might be “legitimizing these products” by continuing to sell them, “providing a false sense of security to prospective consumers.” 

“The FDA might test the products (and) identify the active agents to talk about the risks but the FDA is not going to go into these stores and stop the delivery,” Cohen told El Tecolote. 

El Tecolote reached out to the San Francisco Department of Public Health (SFDPH). Though they acknowledged they had received our inquiry, they did not respond to questions about whether they were aware of the sale of Artri King in the city. 

Living with chronic pain

Four months after quitting Artri King, Caballero is taking ibuprofen and other lower-grade pain medications prescribed for her arthritis. The side effects from the supplement have waned, she said, but her knee pain is back — and debilitating. It now hurts to walk. She continues to work as a house cleaner, pushing through the pain to “not end up on the street.”

Her doctor has acknowledged that, barring surgery, there really is no cure to the pain she feels. It’s something she’ll probably have to live with for the rest of her life. Gloria admits she still has Arti Ajo King pills in her house. 

To her, Artri Ajo King is like every other painkiller: it’s “really good,” but harmful in high doses. In the years that she took it, she emphasized, it made a difference in her quality of life. She remembers them warmly.

Chely, 46, who lives in San Francisco and asked to go by her nickname, wasn’t surprised to learn the pills contained hidden ingredients. When she first started taking Artri King, she said, the effect she felt was so intense that she decided to lower her dosage to one pill per day. The pills help her treat persistent pain in the soles of her feet that she’s had since a fall two years ago. They also give her a rush of energy in the mornings that help her wake up early for work and to walk her dog.

The Mexican house cleaner has been taking the pills since May, but talking to El Tecolote was the first time she learned about the potential side effects. She wondered if her recent hair loss was connected to it. Chely said she planned on looking into the supplements more to decide whether she would keep taking them or not, but didn’t trust a doctor would give her an honest answer.   

Still, she didn’t understand why stores would keep selling them if they were so dangerous. “It’s not fair to harm your people,” she said. 

Chely said she first came across the supplement at Farmacia Internacional on Mission Street, seeking something that could help her alleviate her pain. Walking through the aisles, a dark blue and yellow box caught her eye. It had a picture of part of a skeleton’s hands, with shining orange orbs around the joints.

When she brought it to the counter, the pharmacist told her to adjust the dosage to whatever felt comfortable. Later, she sought the advice of friends, and even a nurse in her Mexican hometown. They all said it would help. 

This story was co-published with El Tecolote and was made possible by the USC Annenberg Center for Health Journalism‘s  “Healing California” initiative, a yearlong Ethnic Media Collaborative with print, online and broadcast outlets across California.