Selank vs. Semax: Which One is Which?

If you have been looking into peptides for your brain, you have probably stumbled across Selank and Semax. They sound like a pair of twins from a spy novel, and they even come from the same place: Russia.

While they both fall into the category of heptapeptides (which is just a fancy way of saying they are chains of seven amino acids), they have very different jobs. Here is the breakdown of what the current data actually says about them.

What is Semax, anyway?

Semax is a synthetic version of a fragment of ACTH. Do not worry about the alphabet soup; basically, it is a piece of a hormone that works on your brain without the side effects that usually come with hormones.

It works by bumping up something called brain-derived neurotrophic factor (BDNF). Think of BDNF as a fertilizer that helps your brain cells grow and stay healthy. It also fiddles with your dopamine and serotonin systems, which are the chemicals in your brain responsible for mood and reward.

What we know about it:

• It has a long history: It has been used in Russia for over 25 years as a standard treatment for ischemic stroke (when blood flow to the brain is blocked).
• It is backed by imaging: Researchers have used fMRI (a brain scan that shows activity) to confirm that it actually does something in there.
• The catch: While Russia has been using it since the 1990s, there is very little evidence from Western clinical trials.

And what about Selank?

Selank is a bit different. It is a synthetic version of something called tuftsin. Instead of just focusing on brain growth, it acts more like a stabilizer.

It works on the GABA-A receptor system. This is the same system that drugs like benzodiazepines (anti-anxiety meds) target. The data suggests it offers similar benefits to those drugs but without the sedation or the risk of becoming dependent on it.

What we know about it:

• It is a multi-tasker: Besides balancing dopamine and serotonin, it may also help your immune system by inducing interferon to fight off viruses like the flu.
• It is a calmer, not a sleeper: It is often compared to benzodiazepines because it helps with balance, but it does not make you drowsy.
• The catch: Most of the evidence comes from Russian clinical practice. Also, because it is usually a nasal spray, scientists are still asking questions about its bioavailability (how much of the stuff actually makes it into your system).

How do they stack up?

Both of these have a Grade B or B- evidence rating. That means there is some solid stuff there, but it is not a slam dunk yet.

• Semax is mainly used for neuroprotection (keeping brain cells safe) and has been a go-to for stroke recovery in Russia for decades.
• Selank is more about normalizing your receptors and could even help your immune system.

Scientists are still working on these — turns out the human body is complicated. Who knew? Neither of these is FDA-approved, though they are both approved for use in Russia.

This is a great one to bring up with your doctor. You can find peptide-experienced physicians in our Find a Doctor directory.

This content is sourced exclusively from TruthTides clinical reference data and does not constitute medical advice.