By Rolfe Winkler

Mark Millich, 26 years old and insecure about his thinning hair, was curious about the ads he saw promising to reverse his hair loss. He completed a 14-question intake on Hims.com and received a bottle of finasteride pills days later. He never spoke to a doctor.

Soon after taking the medicine, Millich said he felt strange symptoms. He woke up one day anxious, dizzy and slurring his words. Later his libido plunged, and his genitals shrank and changed shape. His doctor said the symptoms were caused by the drug. His wife, Marie Linne von Berg, said the symptoms upended their lives.

Finasteride, the generic name for Propecia, is a popular hair-loss treatment that has been on the market for three decades with potential side effects including sexual dysfunction and depression. But a new generation of young men are discovering the medicine -- and its potential risks.

That is largely because they are peppered with ads on social media pitching hair-loss medications from telehealth companies, which unlike drugmakers aren't required to disclose side effects and other risks in advertisements.

It is a loophole telehealth companies have long exploited to sell medicines. More Americans became aware of it during this year's Super Bowl when Hims & Hers Health ran an ad that promoted a weight-loss drug without noting side effects. Two U.S. senators, one of them a physician, protested to the Food and Drug Administration. Telehealth companies say they disclose side effects and other risks on their websites.

Hims last year had $1.5 billion in revenue from more than 2 million customers. The company has a market value of roughly $7.5 billion, even after falling last month on news that it might not be able to continue selling its version of Ozempic.

Dr. Justin Houman, a urologist at Cedars-Sinai Medical Center in Los Angeles, said he has seen a steady increase of young men, one or two a week, seeking treatment for finasteride's sexual side effects. Some also experience panic attacks and suicidal thoughts, he said.

The side effects are "very very common" these days because the medicine is easier to get from telehealth companies, Houman said. He said the cosmetic benefits of finasteride are almost never worth the risks. "This is not something young men should take," he said.

The Wall Street Journal spoke with 17 men, like Millich, who described debilitating side effects from finasteride after getting prescriptions from telehealth companies such as Hims and rival Keeps. Most said they didn't realize there were risks of serious side effects from the hair-loss drug; others said they didn't feel the warnings were adequate.

Hims customers "go through a comprehensive intake that is reviewed by a licensed provider who makes a clinical determination about the patient's eligibility for medication," a Hims spokeswoman said. The company communicates transparently with patients "about all essential details and safety information" and customers can ask clinicians about side effects.

A spokeswoman for Keeps said the company has treated more than one million patients and takes great care to disclose drug side effects on its website, with clinical messaging and on product packaging. "Patient safety and transparency are our top priorities," she said. She said clinical studies show finasteride is effective and side effects are rare. A third telehealth provider, Ro, declined to comment.

Studying side effects

Finasteride was developed by Merck, first to treat enlarged prostate. It has been widely prescribed by doctors to treat male pattern baldness since it was approved for that condition in 1997. Tens of millions of men have taken it since, and prescriptions of it to treat hair loss averaged 175,000 a month in the U.S. in 2024, according to data provider Iqvia. The tally excludes custom versions of the drug that companies such as Hims and Keeps make themselves.

It is an effective drug for regrowing hair and helping young people depressed over their hair loss, said Dr. Anthony Rossi, a dermatologist at Memorial Sloan Kettering in New York. He said he has seen sexual side effects in some patients so "it's important to have a frank conversation with patients." Rossi said he fears telehealth companies don't adequately warn patients about risks and don't do proper exams to establish that finasteride will be effective.

Many men tolerate finasteride well, but some have complications including symptoms that persist after stopping the drug. Propecia's label says 3.8% of patients experienced one or more sexual side effects in Merck's clinical trial, compared with 2.1% who took a placebo.

The Merck clinical trial had flaws and might have underestimated the incidence and severity of sexual side effects, said Dr. Michael Irwig, an endocrinologist at Beth Israel Deaconess Medical Center in Boston. Irwig, who wasn't involved in the clinical trials, criticized them for not following patients long enough or determining whether those with side effects got better, among other reasons.

Regulators have revisited the side effects. In 2011 and 2012, the FDA revised the drug's label to highlight sexual side effects. In 2022, the agency updated the drug's label to include the risk of "suicidal ideation and behavior." The top European drug regulator last fall began reviewing data on a possible link to suicidal behavior. France requires a conspicuous warning about psychiatric and sexual disorders on finasteride packaging.

Merck referred questions to a spin-out company, Organon, that now makes the branded-version of the drug. An Organon spokeswoman said it didn't run the clinical trials, and the company stands behind the drug's safety and efficacy.

Sawyer Hart was 27 and healthy when he got his finasteride prescription from Keeps in 2023. A week in, Hart experienced erectile dysfunction, so he stopped taking the drug. After that, unexplained panic attacks kept him home, and he was later hospitalized.

Hart had used a topical finasteride spray from Keeps. Telehealth companies say the spray has lower risk of side effects than pills. Those claims and products haven't been reviewed by the FDA.

Hart, a materials scientist, wasn't counseled about side effects by his Keeps doctor before he received his prescription, according to his Keeps medical record.

Some men report worsening side effects after stopping finasteride treatment, a condition sometimes called "post finasteride syndrome" that researchers, including Irwig, have described in medical literature.

Irwig said other men likely have symptoms they don't realize are finasteride-related because they and their doctors don't know it can cause them. "Those cases we have are just the tip of the iceberg," said Irwig.

Millich, a former U.S. Army sergeant, hadn't suspected his Hims finasteride prescription was at fault, since the first symptoms were cognitive, including insomnia and depression.

After their telehealth care, both Hart and Millich saw new doctors. Each of them told the Journal that they determined their patients' symptoms were triggered by finasteride. Spokeswomen for Keeps and Hims declined to comment about Hart's or Millich's care.

'Personalized' drugs

Hims launched in 2017 to sell hair-loss and erectile dysfunction drugs. Patients complete a medical questionnaire, select a drug they want, and clinicians review the information before prescribing. Drugs come by mail. Clinicians communicate via messages in its app.

Hims and its rivals charge customers for drugs, not medical consults, unlike traditional medicine where doctors get paid whether they prescribe or not and send prescriptions to pharmacies.

The telehealth firms run hair-loss ads that target men in their 20s and 30s. A young woman runs her fingers through a man's full head of hair in an Instagram ad. A TV ad promises to help young men "break tradition" of hereditary hair loss. To appeal to consumers, Hims pills have bright colors and its chewables undergo taste tests.

Hims markets "personalized" drug formulations it designs and makes itself so it can retain customers, the company has said. One combines finasteride with an erectile dysfunction drug Hims calls "Sex Rx + Hair Hero."

The Hims spokeswoman said personalized treatments use drug ingredients that have individually been tested for safety and that appealing tastes and colors encourage patients to adhere to the medication schedule laid out by their clinicians.

Testing the telehealth process

The Journal reviewed the prescription process for Hims, Keeps and Ro.

Ro warns patients about finasteride's potential side effects before the drug is prescribed. It notes the roughly 4% of men who experienced one or more symptoms of sexual dysfunction during the drug's clinical trial.

On Keeps's website, a customer had to click through two optional links to find finasteride risks where the 3.8% rate of sexual side effects was listed.

The Hims intake process included optional disclosures that used a different percentage range for sexual dysfunction, 1.2% to 1.4%. That was the same range that was shown to Millich when he got his prescription five years ago, his Hims medical records show.

The Hims spokeswoman initially said the disclosure was reviewed by its medical team, but later said there was a "typo." The same numbers appeared in the company's clinician training manual, which the Journal reviewed.

The company's intake process also says: "In clinical trials, a small number of men experienced certain sexual side effects on finasteride, each occurring in less than 2% of men." Those were the rates of individual sexual side effects, such as erectile dysfunction, in Merck's clinical trial.

Former Hims employees described side-effect information as "friction" that stops some customers. For the same reason, the company stopped requiring hair-loss patients to upload photos of their scalp, the former employees said. Keeps and Ro both require scalp photos.

Some Hims clinicians described misgivings, including Dr. Jonathan Daly, an internal medicine physician, who worked for Hims for two years. "I just felt like as a platform, it was more of the let's go ahead and prescribe, get as many patients as we can to use medications from us," he said.

The Hims spokeswoman said its systems help clinicians make decisions quickly by flagging if a patient's case is routine or more complex, that clinicians can request scalp photos if they deem it necessary and that clinicians are still paid if they choose not to prescribe.

When a Journal reporter tested Hims's service, he submitted his intake at 11:18 a.m. A follow-up text said his finasteride prescription was written at 11:19 a.m.

Write to Rolfe Winkler at Rolfe.Winkler@wsj.com

(END) Dow Jones Newswires

March 13, 2025 05:30 ET (09:30 GMT)

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