Gels dominate the market for transdermal testosterone replacement therapy — "presumably because of their greater patient acceptability and non-occlusive nature compared with patches."[1] That is the whole explanation the pharmaceutical-science literature offers, and it is worth noticing what is absent from it: any claim of better pharmacokinetics.
This page's slug carries a revenue figure. It is not asserted here — no source consulted for this hub states it, and unverifiable numbers get dropped rather than repeated. The market outcome is documented; the dollar amount is not.
Winning on tolerability, not on pharmacology
The sequence is clear enough. Early transdermal patches arrived in the 1980s, with gel and solution preparations following in subsequent decades.[1] The gels then took the market.
Both reasons given are about how it feels to use, not how it performs in the blood:
Patient acceptability. No adhesive, no visible patch, no site preparation.
Non-occlusive. Nothing sealed against skin for hours, which is the mechanism behind patch irritation.
That is a genuine clinical advantage, just not the kind usually advertised. Adherence to topical testosterone in routine care is low, and adherent men show greater increases in testosterone and better outcomes.[2] A formulation people tolerate is a formulation that works more often.
The cost of winning
Market dominance put a lot of testosterone onto a lot of skin, and that produced the category's defining problem. Specific incidences of secondary transfer of gels to children, with consequent unwanted effects such as precocious puberty, have been reported.[1]
This is not a rare theoretical concern. It is serious enough to carry an FDA boxed warning — the agency's most severe labelling requirement — describing virilization in secondarily exposed children, with most signs regressing on removal of exposure, but in a few cases enlarged genitalia not fully returning to age-appropriate size and bone age remaining modestly advanced.[4]
The next episode is that warning: when gels transfer.
The regulatory turn
Hadgraft and Lane, writing in 2015, note that a regulatory review of all testosterone replacement therapies was then underway, which might have implications for future prescribing practices of transdermal products.[1]
That review's most visible outcome for patients arrived later: the FDA issued class-wide labeling changes for testosterone products in February 2025.[5] The market that gels built is the market regulators went on to re-examine.
Frequently asked questions
Why did gels beat patches? Patient acceptability and their non-occlusive nature, per the pharmaceutical-science literature.[1]
Are gels pharmacokinetically better than patches? That is not the stated reason for their dominance.[1] The guideline treats pharmacokinetics as one of five considerations rather than a ranking.[3]
What is the main downside of a gel? Transfer to other people — documented, labelled with a boxed warning, and largely preventable with the labelled precautions.[1][4]
Did the revenue really reach a billion? Not something this hub asserts. No source consulted here states it.
Next in this series
The transfer problem is the reason testosterone gel carries the FDA's most serious warning — and the warning is not about the man using it.
Continue with the boxed warning.
References
5 sources
- Hadgraft J, Lane ME. Transdermal delivery of testosterone. Eur J Pharm Biopharm. 2015;92:42–48. doi:10.1016/j.ejpb.2015.02.015 · PMID 25709060
- Grabner M, Hepp Z, Raval A, et al. Topical Testosterone Therapy Adherence and Outcomes Among Men With Primary or Secondary Hypogonadism. J Sex Med. 2018;15(2):148–158. doi:10.1016/j.jsxm.2017.11.225 · PMID 29425664
- Bhasin S, Brito JP, Cunningham GR, et al. Testosterone Therapy in Men With Hypogonadism: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2018;103(5):1715–1744. doi:10.1210/jc.2018-00229 · PMID 29562364
- U.S. Food and Drug Administration. AndroGel (testosterone gel) 1% — prescribing information, including BOXED WARNING: secondary exposure to testosterone. Reference ID 021015s044. 2019. accessdata.fda.gov
- U.S. Food and Drug Administration. FDA issues class-wide labeling changes for testosterone products. February 28, 2025. fda.gov
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