For now, Maryanne Senna, a dermatologist and the director of the Hair Academic Innovative Research Unit at Massachusetts General Hospital in Boston, said the best she can tell patients who ask — and a lot of them do — is that Harklinikken won’t do any harm.
“Don’t get me wrong — I really want it to work,” said Dr. Senna, who also teaches at Harvard Medical School. “There aren’t a lot of options, and I’d love to be able to say to my patients, ‘This is something you can try that is worth the money.’ But I can’t do that yet.”
Harklinikken’s formula, refined over 20 years, is derived from plants and cow’s milk. That’s the most Mr. Skjoth will say about it. In the 1990s, clients mixed it with Rogaine, Mr. Skjoth said, “and then we took the Rogaine part away and started focusing on the actual liquid.”
Small studies have shown the efficacy of various plant-derived ingredients, mostly in mice. But two potential explanations for Harklinikken’s success have little to do with its formula.
One is how much emphasis the company places on compliance, the major stumbling block in the efficacy of any treatment, said Dr. Senna, an author of studies on the subject. Prospective users are questioned about their ability to stick to a regimen because the extract must be applied every day, and they are told that the more conscientious they are, the better. Users are also reminded and encouraged with regular check-ins.
Clients must also use the company’s shampoo, conditioner and styling products, forsaking all others — a psychological as well as a financial buy-in, Dr. Senna said. (Mr. Skjoth, who has a master’s degree in nutrition and chemistry but is not a doctor, said this is because other products may clog the scalp, causing hair loss.)
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Hair changes about as fast as grass grows, which is to say it’s extraordinarily slow and not visible to anyone checking impatiently in the mirror every day. But during regular follow-up appointments, Harklinikken uses high-tech equipment to photograph and magnify the scalp and count new hairs and active follicles, which motivates users to adhere to the regimen. Too many people give up on treatments like Rogaine and low-level-light devices before they’ve had a chance to work, Dr. Senna said.
It’s also possible that some of Harklinikken’s users are women whose hair would have grown back even if they’d done nothing. Many women who arrive in a dermatologist’s office with prior diagnoses of female pattern hair loss actually have what’s called telogen effluvium. That’s a period of acute shedding of hair — meaning up to 60 percent of hair — three months after a triggering event like pregnancy, significant weight loss or starting or stopping hormone medications.