Semax and selank on TikTok: separating hype from thin evidence

What did @simplykim843 actually say?

The creator describes a morning peptide routine of semax, selank, and NAD, and says she dropped SS-31 after identifying it as the source of her headaches. Her headline claim is direct: "that combination has helped with my anxiety, my depression, my ADHD, my brain fog, all of the things." She also credits the stack for energy, which she says gets her up at 5 a.m. That is a lot of ground covered for two peptides most clinical researchers have barely started studying in Western settings. To her credit, she does not claim a cure, does not name a dose, and she did the right thing by eliminating one compound at a time to identify the culprit. That is actually reasonable self-experimentation methodology. But the symptom list she rattles off deserves serious scrutiny.

Does the science back this up?

Partially, and with major caveats. The existing research on semax and selank is real but narrow, mostly Russian, and rarely replicated in Western peer-reviewed journals. Semax is an ACTH-derived synthetic peptide studied for its effects on BDNF expression and cognitive function. Selank is a tuftsin analogue that has shown anxiolytic properties in a handful of trials. But "handful" is doing a lot of work in that sentence.

• Semax has shown increases in BDNF in animal models and some small human studies (Dolotov et al., 2006, Neurochemical Research), which could theoretically support mood and cognition. Theoretically.
• Selank demonstrated anxiolytic effects comparable to low-dose benzodiazepines in a small Russian trial (Semenova et al., 2010, Bulletin of Experimental Biology and Medicine), with fewer sedating side effects. That is genuinely interesting, but the sample sizes were small and the studies were not blinded to Western standards.
• NAD precursors have a broader evidence base for energy metabolism and mitochondrial function (Rajman et al., 2018, Cell Metabolism), though the oral bioavailability debate for NAD itself is ongoing.

Saying these peptides "help" with ADHD specifically has almost no published support. ADHD is a neurodevelopmental condition. Claiming a peptide addresses it is a significant overreach from the available data.

What did they get wrong (or right)?

Credit where it is due: attributing her headaches to SS-31 by process of elimination, rather than just stopping everything or pushing through, shows more methodological discipline than most self-experimenting creators online. SS-31 (elamipretide) is a mitochondria-targeting peptide, and headache is a documented side effect in clinical trial participants (Daubert et al., 2017, JACC: Basic to Translational Science). Her troubleshooting was reasonable.

What she got wrong, or at minimum overclaimed, is the symptom list. Saying a combination "helped with my anxiety, my depression, my ADHD, my brain fog, all of the things" in one breath collapses conditions that have distinct neurobiological profiles into a single anecdote. Depression and ADHD alone have overlapping but different pathophysiology. Even if she genuinely feels better, four confounders nobody in the comments will consider: sleep quality changes, placebo effect, regression to the mean, and the fact that she also takes NAD, which has its own metabolic effects. Attribution here is not clean.

What should you actually know?

Semax and selank are not FDA-approved for any indication in the United States. They exist in a legal gray zone, often compounded by peptide pharmacies operating under varying regulatory oversight. That does not make them automatically dangerous, but it does mean quality control is not standardized and the risk profile is not fully mapped in large-scale human trials.

A few things worth keeping in mind before you replicate this stack:

• Neither peptide has been tested in long-term human trials for anxiety or depression as stand-alone endpoints in Western regulatory frameworks.
• "Anxiolytic" in a Russian Phase II trial and "fixed my anxiety" in daily life are not the same claim.
• If you are already on an SSRI, SNRI, or stimulant for ADHD, adding peptides that modulate BDNF or GABA-adjacent pathways without clinical oversight is a real drug-interaction risk that no TikTok video can account for.
• The headache resolution she describes after stopping SS-31 is consistent with published trial data. That part checks out.

Bottom line: the individual peptides she names have plausible mechanisms and early-stage evidence supporting some of what she describes. But the leap from "plausible mechanism" to "fixed my ADHD and depression" is exactly the kind of gap that gets people in trouble when they self-treat serious mental health conditions without professional oversight.