Dr. Kallonen's testosterone and hair loss claim, fact-checked

What did @breannekallonen actually say?

The creator, identifying herself as a clinician reviewing actual lab results, argued that testosterone pellet therapy in women can push androgen levels into "super physiological" territory, causing side effects like hair loss. Her specific concern: pellet dosing is difficult to titrate, meaning levels spike even higher right after a new pellet is inserted. She pointed to elevated total testosterone, free testosterone, and dihydrotestosterone (DHT) in one patient's labs, taken at the trough, the lowest point before the next pellet, as evidence the dosing was too aggressive. Her core claim is that benefits like energy and libido don't justify the androgenic side effects when hormones exceed normal physiological ranges.

This is a clinically grounded argument, not a TikTok scare story. She is describing a real pharmacokinetic problem with a specific delivery method, not claiming testosterone is inherently dangerous for women.

Does the science back this up?

Yes, largely. The pharmacokinetic criticism of pellet therapy is well-documented and is one of the more legitimate clinical objections to this delivery method. The concern is real and backed by peer-reviewed data.

Subcutaneous testosterone pellets produce supraphysiologic androgen levels in a meaningful percentage of women. A 2012 study by Glaser and Dimitrakakis published in Maturitas reported that while pellets improved symptoms in postmenopausal women, monitoring was essential because dosing variability was significant. More directly, a 2019 retrospective analysis by Pattimakiel and Thacker in Cleveland Clinic Journal of Medicine flagged pellets for producing inconsistent serum levels compared to transdermal methods. The Endocrine Society's 2019 clinical practice guidelines for testosterone therapy in women explicitly note that pellet implants carry a risk of supraphysiologic testosterone concentrations and that levels are not easily reversible once implanted.

The DHT connection to androgenic alopecia is also solid. DHT binds to androgen receptors in scalp follicles and is a well-established driver of pattern hair loss in genetically susceptible individuals (Starace et al., 2021, Dermatology and Therapy).

What did they get wrong (or right)?

She got the core pharmacology right. The claim that pellets produce difficult-to-control androgen spikes is accurate, and the DHT-hair loss pathway is not in dispute. She also correctly noted that trough labs, meaning levels at their lowest point, still showed supraphysiologic values, which is a legitimate red flag in hormone management.

What she does not address, and this matters, is that hair loss from androgens in women is heavily influenced by genetic susceptibility. Not every woman on pellet therapy will lose hair, even at similar androgen levels. The risk is real but not universal, and framing it as an inevitable consequence of pellets oversimplifies the picture somewhat.

She also presents one patient's case. That is a case report, not a population-level finding. It is illustrative, but viewers should understand this is one data point, not an epidemiological pattern she is describing from a clinical trial.

Still, her skepticism of pellets as a delivery method for women is defensible. The irreversibility problem alone, you cannot remove a pellet the way you can stop a cream or patch, makes overshoot a meaningful clinical risk.

What should you actually know?

If you are considering or currently on testosterone therapy as a woman, delivery method matters clinically, not just in theory. Transdermal testosterone, applied as a cream or gel, allows for dose adjustments that pellets simply do not. This flexibility is especially important during the initial dose-finding phase.

Normal physiological testosterone ranges for premenopausal women are generally considered to be between 15 and 70 ng/dL for total testosterone, though reference ranges vary by lab. "Super physiological" means above that range, and the androgenic side effects, including acne, clitoral enlargement, voice changes, and yes, hair loss, become more likely as levels climb higher and stay there.

Hair loss specifically depends on your androgen receptor sensitivity and your genetic predisposition to androgenic alopecia. If pattern hair loss runs in your family, elevated DHT is a more serious concern for you personally than it might be for someone without that history.

Any clinician managing your testosterone therapy should be running follow-up labs, including free testosterone and DHT, not just total testosterone, and adjusting accordingly. If they are not, that is worth raising directly.