NAD injections for energy and longevity: what the evidence says

What did @copiousaf actually say?

She's using a nasal spray combining semax and selank, taking it fasted in the morning, and genuinely unsure whether she's feeling anything. She expected effects "in 15 to 30 minutes" and wonders if, like GHK-Cu, it needs weeks to build up before you notice anything. Credit where it's due: she's not overselling this. The uncertainty is honest.

She also notes that she was told the nasal spray is "the more potent form" compared to injection, which is a specific pharmacokinetic claim worth examining. She's asking her audience whether results required a month of consistent use rather than a single-dose hit, which is actually a reasonable question given how these peptides work in animal models.

Does the science back this up?

Here's the short answer: semax and selank both have real research behind them, but almost none of it involves healthy Western users self-administering nasal sprays bought online. That gap matters enormously.

Semax is a synthetic analogue of ACTH(4-7), originally developed in Russia in the 1980s. It has been studied for neuroprotection and cognitive function, primarily in stroke and neurological patients. Zozulya et al. (2006, CNS Drug Reviews) reviewed its mechanisms and noted BDNF-stimulating effects in rodents and limited human trials focused on brain injury recovery, not healthy optimization. Selank is a synthetic analogue of tuftsin, studied for anxiolytic effects. Semenova et al. (2010, Bulletin of Experimental Biology and Medicine) showed reduced anxiety and improved memory in animal models. Human data is thin and mostly from Russian clinical registries, not large randomized controlled trials.

The "nasal spray is more potent than injection" claim has a plausible pharmacological basis: intranasal delivery can bypass the blood-brain barrier via olfactory pathways, potentially delivering peptides more directly to CNS tissue. But "more potent" and "same bioavailability" are different claims. No peer-reviewed head-to-head comparison in humans exists to confirm this definitively.

What did they get wrong (or right)?

She got the uncertainty right. Semax and selank are not fast-acting stimulants. Expecting a noticeable shift "in 15 to 30 minutes" is based on anecdote, not clinical trial data. The studies that do exist measure effects over days to weeks, not minutes.

Her comparison to GHK-Cu needing saturation time is directionally reasonable. Peptides that influence neuroplasticity or BDNF expression don't flip a switch in 20 minutes. That said, the "saturation" framing isn't precise pharmacology. What she's likely describing is cumulative receptor sensitization or downstream gene expression changes, neither of which is guaranteed in a healthy brain that isn't in a deficit state to begin with.

The fasted-state point is genuinely unclear for intranasal peptides. Fasting matters for oral bioavailability. For nasal administration, gastric emptying is irrelevant. Enzymatic degradation in nasal mucosa is the bigger variable, not what you ate for breakfast. This is a minor but real misconception.

What should you actually know?

Semax and selank are not FDA-approved in the United States. They are not banned substances, but they are not approved medications either. Compounded or research-grade versions vary widely in purity, concentration, and sterility, and no regulatory body is verifying what's in that nasal spray bottle.

If you're experiencing subtle effects that feel like "calmness and a quietness in the mind," that could reflect genuine anxiolytic activity consistent with selank's GABA-modulating properties, or it could be expectation bias. Both are real phenomena. The absence of a blinded control in self-experimentation makes distinguishing them nearly impossible.

The honest clinical picture: these peptides show promising early-stage research in specific patient populations, largely in Russian literature that hasn't been independently replicated at scale. Using them for healthy optimization is extrapolation from animal data and small human trials. That doesn't mean zero benefit, but it does mean you should not expect a clean answer from your social media comment section either.

• No human RCT has established an effective dose or administration protocol for semax or selank in healthy adults.
• Nasal route does have theoretical CNS delivery advantages, but "more potent than injection" is unconfirmed in peer-reviewed human data.
• If you're considering these compounds, a licensed clinician familiar with peptide pharmacology should be involved.