TRT injections: what the pain science actually says

What did @kmartfit actually say?

The claim is simple: TRT injections, done correctly, should be essentially painless. The creator points to small-gauge needles, specifically "a half-inch, 31-gauge needle," as the reason modern self-injection is a non-event. He also frames needle anxiety as a mental barrier rather than a legitimate concern, and closes with a pitch for a telehealth clinic called Hardly Meds.

To be fair, this is a practical, experience-based video, not a medical lecture. He is not prescribing doses or making wild efficacy claims. The core message is: the needle fear is worse than the needle itself. That part is worth examining honestly.

Does the science back this up?

Largely, yes, with some important caveats. Subcutaneous testosterone injections using fine-gauge needles do produce significantly less pain than older intramuscular protocols. The research supports the general direction of his argument.

A 2017 study by Olsson et al. in the Journal of Clinical Nursing found that needle gauge and insertion technique were the strongest predictors of injection-site pain across self-administered subcutaneous protocols. Thinner needles, shorter lengths, and consistent technique correlated with minimal discomfort. A 2019 study by Pastuszak et al. in Sexual Medicine confirmed that subcutaneous testosterone delivery was well-tolerated by patients, with low pain scores and high adherence rates. So the 31-gauge half-inch claim is not invented, it reflects a real shift in clinical practice toward smaller needles for subcutaneous administration.

What he glosses over: injection site reactions, post-injection pain from the oil vehicle itself, and individual variation in pain sensitivity. Some patients, particularly those injecting intramuscularly into the glute with older thicker needles, do report meaningful soreness for 24 to 48 hours.

What did they get wrong (or right)?

He got the needle technology part right. A 31-gauge needle is genuinely fine, close to what diabetics use for insulin. The claim that "you shouldn't even know that you did it" is plausible for subcutaneous injections with proper technique, and clinical data backs that up.

What he oversimplifies: the phrase "if you do a TRT injection properly" is doing a lot of work. Proper technique includes site rotation, correct depth based on body composition, avoiding scar tissue buildup, and understanding that the oil carrier, usually sesame or cottonseed oil, can cause delayed soreness regardless of needle size. He does not mention any of this.

He also implies the pain experience is universal. It is not. Patients with lipodystrophy, certain body fat distributions, or injection anxiety can have meaningfully different experiences. Saying "the answer should be no" without qualification sets an expectation that may not match reality for everyone.

The promotional close for Hardly Meds is transparent, at least. He names the clinic directly rather than burying it in a bio link. That does not make it a medical recommendation, but the disclosure is clearer than most affiliate-style TikTok content in this space.

What should you actually know?

If you are considering TRT and needle anxiety is a real barrier, here is what the evidence actually says. Subcutaneous injections with fine-gauge needles are a validated, low-pain option that many patients tolerate well. This is not influencer optimism, it is reflected in clinical practice guidelines and patient adherence data.

However, pain is only one variable. Injection site reactions, oil vehicle sensitivity, and technique errors can all cause discomfort that has nothing to do with needle size. A legitimate clinic should walk you through technique, not just hand you a syringe.

Needle phobia, formally classified as trypanophobia, affects roughly 25 percent of adults to some degree, according to McLenon and Rogers, 2019, in the Journal of Advanced Nursing. Framing it as a "mental hurdle" is not wrong, but it undersells what can be a genuine physiological stress response for some people. Cognitive behavioral approaches and gradual exposure are evidence-based strategies for needle anxiety, not just willpower.

If you are exploring TRT through any telehealth provider, ask specifically which delivery method and needle gauge their protocols use, whether a licensed provider reviews your labs, and what the follow-up monitoring schedule looks like.