Glutathione vs Selank
It is sold as an antioxidant booster, for skin lightening drips and for detox. One small trial showed slight lightening at two skin sites, and trials for other uses failed. It is sold as a nose spray to calm anxiety and sharpen focus. The only trial, in Russia, had 62 patients and no placebo group, so it proves little.
Both sit at grade B: some human evidence. Neither is FDA approved.
Evidence
BSome human evidence
BSome human evidence
Human studies cited
Animal or cell studies cited
Why the grade
For skin lightening, the use glutathione is most often sold for, there is one randomised placebo-controlled trial of oral glutathione in 60 healthy students that found a small drop in melanin index at two of six skin sites. The larger trials in hand were for other purposes: a 153-patient inhaled trial in cystic fibrosis that missed its primary endpoint, a 54-adult trial showing oral glutathione raises blood levels, and a 21-patient Parkinson's pilot. No trial of intravenous glutathione for skin exists.
There is one small controlled comparison in 62 patients with generalized anxiety disorder or neurasthenia, published in Russian without a placebo arm, plus a cytokine study in a subset of patients and two animal or in vitro studies on GABA and NMDA receptor binding. One controlled human trial meets the letter of B, but it is tiny, the abstract reports neither randomization nor blinding, and it has never been replicated outside Russia.
FDA
Not approved
Glutathione is not approved by the FDA as a drug for any indication. Oral glutathione is sold as a dietary supplement, intravenous and inhaled forms are made by compounding pharmacies, and glutathione sits in Category 1 of the FDA's list of nominated compounding substances, meaning it may be compounded while the agency evaluates it. In August 2026 the agency warned compounders not to use supplement grade glutathione in injectables after a cluster of adverse events.
Not approved
Selank is not approved by the FDA for any use and is sold in the United States as a research chemical. It is registered as a prescription anxiolytic in Russia. It is not on the FDA's list of substances pharmacies may compound, and it was not among the peptides the FDA's compounding advisory committee reviewed in July 2026.
Sold for
Glutathione is sold as a master antioxidant, for skin whitening by intravenous drip, for detox and for Parkinson's disease.
Selank is sold as a nasal spray that calms anxiety without the sedation or dependence of benzodiazepines and sharpens focus at the same time.
Studies say
Oral glutathione does raise body stores and produced a modest, site-specific lightening in one small trial, while inhaled glutathione failed in cystic fibrosis and intravenous glutathione showed no clear benefit in a Parkinson's pilot, so the grade is B for the skin claim and lower for the others.
A single 62-patient Russian trial found anxiety relief comparable to a benzodiazepine, and animal work points to GABA and NMDA receptor effects, but there is no placebo-controlled human trial, so the claims rest on thin evidence.
Class
Antioxidant tripeptide
Anxiolytic peptide (Russian)
Route
Several routes
Nasal