Semax is a peptide used by some people to improve working memory, focus, and learning. But is it an effective aid for studying or other cognitively demanding tasks? Read on to find out what the strongest science available says.

This nootropic has no healthy human placebo-controlled studies that meet our inclusion criteria. Negative side effects can occur if used carelessly, so make sure you’re aware of the risks of Semax.


Read about the effects of Semax in relation to the amount of evidence we've found

Semax for cognitive enhancement

There is no scientific data available on the efficacy of Semax for cognitive enhancement in healthy humans.

In one study, 30 stroke patients received Semax for 5-10 days. [1] The authors concluded that 12 mg (route of administration undefined) was the most effective dose for patients with moderate severity strokes and that 18 mg (route of administration undefined) was the most effective dose for patients with severe strokes. They concluded that Semax effectively helped in restore healthy brain function. However, this study should be interpreted carefully since its results cannot say a lot about the efficacy of Semax for brain function improvement in healthy humans without stroke.

In another study, 187 patients with cerebrovascular insufficiency were examined. [2] The study authors concluded that Semax improved "... stabilization of the disease progress and reduced a risk of stroke". However, the full text is not available online, and very few details exist about the methodology of this study. Although the results are positive, this study is of low relevance to healthy people looking to enhance cognition because of severe data quality problems.

The authors of a third study reported that "Semax significantly improves memory and attention in healthy men under extreme conditions of activities." [3] The full text of this study is not available online, which means the validity of this statement cannot be critically analyzed.

There are also some animal studies supporting the efficacy of Semax as a cognitive enhancer. [5][6]

To conclude, Semax may be an effective cognitive enhancer for healthy humans, or it may not effectively improve cognition. The science that does exist suggests that it has the potential to improve cognitive performance, but the evidence is of very low quality and relevance to healthy humans.

Semax for improved quality of life

Semax has been examined in one study with some relevance to healthy people looking to improve their quality of life. Semax was given intranasally (by use of nasal spray, presumably) to patients with motor neuron disease in "... two 10-day-long courses with 2-weeks break ...", with the daily dose being 12 mg. [7]

The peptide did not improve the primary outcome measure of the study: symptoms of motor neuron disease. But it did improve estimated quality of life thanks to improved emotional state and motivation, the authors concluded. The effect was strongest after 10 days. The reason this result is quite useful for healthy people is because the improved quality of life is likely not due to any disease changes. However, the baseline quality of life of the study participants is not defined in the study abstract, and the full text is unavailable online. This means that there is a risk that these patients had a low baseline quality of life, and that Semax would not improve the quality of life for healthy humans who already feel meaning and well-being.

In one study, Semax didn't improve disease symptoms, but did improve quality of life. This means it improved QOL independently of disease progression, which entails that there is also a possibility of beneficial effects for healthy humans looking to improve their life with Semax. Data from healthy humans needs to be collected to confirm such an effect before it can be considered science-backed to use Semax for QOL improvement as a healthy person.


The legality and side effects of Semax


Frequently asked questions about Semax


Studies conducted on the effects of Semax in healthy humans

Last updated Saturday, June 10, 2023