Sunifiram

What it is

Chemically, sunifiram is a piperazine ring with two small acid residues attached, a benzoyl and a propionyl residue. It originated at the University of Florence. The group around Manetti, Ghelardini and Gualtieri was looking for relatives of piracetam, the oldest nootropic, and first found unifiram, lab name DM232. In 2000 they showed that its ring system can be simplified without losing the effect in animals. The strongest product of this simplification was DM235, later named sunifiram.

The developers themselves call their substances Unifi nootropics, after the abbreviation of their university. There was no patent protection for the substances; around 12 years after the first description, Gualtieri found them offered on dozens of websites as memory aids for healthy people. Sunifiram shares its effect profile in animals with piracetam, but the chemical relationship is loose: the pyrrolidone ring typical of piracetam is missing.

How it is supposed to work

The first trail led to the AMPA receptors. These are docking sites for the messenger glutamate that transmit fast signals between nerve cells and are central to storing memories. In mice, sunifiram reversed forgetfulness that had been deliberately induced by the AMPA blocker NBQX, and in rat brain slices it acted in a way that NBQX reversed. The Florence group therefore places sunifiram close to the ampakines.

A Japanese research group around Shigeki Moriguchi at Tohoku University arrived at a second mechanism in 2013. In mouse brain slices, sunifiram enhanced long-term potentiation, the cellular model of learning, via the glycine-binding site of the NMDA receptor. From there the signals ran on via the enzymes PKC-alpha and CaMKII, which enhance AMPA and NMDA receptors. When the glycine site was blocked, the effect disappeared.

In addition there is an effect on acetylcholine, the messenger that is the first to decline in Alzheimer’s disease. In the rat cerebral cortex, sunifiram doubled acetylcholine release 45 minutes after administration. Notably, at higher doses this effect was absent, and the enhancement of long-term potentiation also followed a bell-shaped curve. Classic receptor binding, by contrast, was not found.

Sunifiram and Noopept

Both are traded as piracetam relatives, both with the formula a thousand times stronger. In both cases this refers to the effective dose in animal experiments, not to the effect being stronger. That is where the similarities end. Noopept is a dipeptide, approved as a medicine in Russia and studied in patients with mild cognitive impairment, albeit without a placebo comparison. Sunifiram is a piperazine molecule without approval, for which there is not a single study in humans.

What users report

In the nootropics scene, sunifiram is nevertheless well known. A 2025 review describes it as easily available from online retailers, often with a purity certificate, and forums as platforms on which users exchange their experiences as if in self-organized trials. These reports are uncontrolled. How many people take sunifiram has not been recorded.

What the studies show

Ghelardini et al., Naunyn-Schmiedeberg’s Archives 2002

The central animal study. In mice in the avoidance test, sunifiram prevented forgetfulness caused by scopolamine, mecamylamine, baclofen and clonidine, after injection as well as after oral administration. In the water maze it protected rats from scopolamine-induced learning impairment. Motor coordination and spontaneous behavior remained unchanged. The authors estimate the potency at about 1,000 times that of the most active piracetam-like substances.

Galeotti et al., Naunyn-Schmiedeberg’s Archives 2003

Specifically tested the AMPA hypothesis. Sunifiram reversed the forgetfulness induced by the AMPA blocker NBQX in mice. In rat hippocampal slices it reversed an inhibition of NMDA-mediated neurotransmitter release, and this effect disappeared under NBQX.

Moriguchi et al., Hippocampus and Behavioural Brain Research 2013

Two papers by an independent group. In brain slices, sunifiram enhanced long-term potentiation via the glycine-binding site of the NMDA receptor. In mice with removed olfactory bulbs, administration over 7 to 12 days improved memory tests and restored long-term potentiation; depression-like behavior did not improve.

Where the data stop

The line is clearly drawn: there is not a single study in humans, and none is registered in the ClinicalTrials.gov registry either. Sunifiram never entered clinical development. How it is absorbed and broken down in humans, whether it reaches the same receptors there and whether it has any effect at all in healthy people, nobody knows. Published toxicity studies are missing; the former head of the developer group, Fulvio Gualtieri, wrote in 2016 that the long-term toxicity is unknown.

The animal data also have limits. What was measured was almost always whether sunifiram prevents an artificially induced forgetfulness. In animals without memory impairment it showed no improvement in the standard test, only in a social learning test. The bell-shaped curves mean that more did not bring more effect in animals. And the two mechanisms, AMPA enhancement and the NMDA glycine site, have to this day not been brought together into one picture.

Status, approval and legal

Sunifiram is not approved anywhere as a medicine and in the EU is neither a food nor a food supplement; it is traded as a research chemical. It is not listed in the German Narcotics Act, and by its structure it does not fall into any of the substance groups of the New Psychoactive Substances Act. In the US it is not approved either; in 2023 the drug authority FDA imposed a 5-year import ban on an importer who had imported sunifiram among other things. In sport, sunifiram is not named on the World Anti-Doping Agency’s 2026 Prohibited List. As a substance not approved anywhere, it falls under S0 according to the wording and is thus prohibited at all times; a 2025 analysis also considers a classification under the stimulants S6 possible, based on its similarity to 4-phenylpiracetam.

Safety

All safety information comes from animal experiments. There, at the effective doses, sunifiram disturbed neither coordination nor movement or exploratory behavior, and according to the developers’ review not even at 1,000 times the smallest effective dose. Systematic toxicity studies, data on side effects in humans and on interactions do not exist. A 2025 review calls the long-term safety poorly understood. Because sunifiram intervenes in the glutamate signaling pathways, there are no data at all, particularly for people with epilepsy or psychiatric disorders, nor for pregnant or breastfeeding women, children and adolescents. Gray market products are unverified in purity and content. Persistent memory problems should be clarified by a physician.

Sources

• Manetti et al., Journal of Medicinal Chemistry 2000 – piperazine derivatives with high nootropic activity (first description of DM235)
• Ghelardini et al., Naunyn-Schmiedebergs Archives of Pharmacology 2002 – DM235 (sunifiram) as a new nootropic
• Galeotti et al., Naunyn-Schmiedebergs Archives of Pharmacology 2003 – AMPA receptors and the antiamnesic effect
• Romanelli et al., CNS Drug Reviews 2006 – pharmacological characterization of unifiram and sunifiram
• Moriguchi et al., Hippocampus 2013 – sunifiram and the glycine-binding site of the NMDA receptor
• Moriguchi et al., Behavioural Brain Research 2013 – sunifiram in mice with removed olfactory bulbs
• Gualtieri, Journal of Enzyme Inhibition and Medicinal Chemistry 2016 – Unifi nootropics from the lab to the web
• Vialko et al., International Journal of Molecular Sciences 2025 – AMPA and kainate modulators, review
• Pokrywka et al., Biology of Sport 2025 – brain doping substances and the WADA list
• FDA, Federal Register 2023 – import ban against a nootropics importer