# 25H-NBOMe

25H-NBOMe (NBOMe-2C-H) is a derivative of the phenethylamine hallucinogen 2C-H, which acts as a highly potent full agonist for the human 5-HT$_{2A}$ receptor.

## Pharmacology

25H-NBOMe acts as an agonist of the serotonin 5-HT$_2$ receptors. In accordance with its psychedelic effects in humans, it produces the head-twitch response, a behavioral proxy of psychedelic effects, in rodents. The drug has also been found to produce antidepressant-like effects in rodents.
25H-NBOMe has shown reinforcing effects in rodents. This included conditioned place preference (CPP) and self-administration.

## Toxicity and harm potential

NBOMe compounds are often associated with life-threatening toxicity and death. Studies on NBOMe family of compounds demonstrated that the substance exhibit neurotoxic and cardiotoxic activity. Reports of autonomic dysfunction remains prevalent with NBOMe compounds, with most individuals experiencing sympathomimetic toxicity such as vasoconstriction, hypertension and tachycardia in addition to hallucinations. Other symptoms of toxidrome include agitation or aggression, seizure, hyperthermia, diaphoresis, hypertonia, rhabdomyolysis, and death. Researchers report that NBOMe intoxication frequently display signs of serotonin syndrome. The likelihood of seizure is higher in NBOMes compared to other psychedelics.
NBOMe and NBOHs are regularly sold as LSD in blotter papers, which have a bitter taste and different safety profiles. Despite high potency, recreational doses of LSD have only produced low incidents of acute toxicity. Fatalities involved in NBOMe intoxication suggest that a significant number of individuals ingested the substance which they believed was LSD, and researchers report that "users familiar with LSD may have a false sense of security when ingesting NBOMe inadvertently". While most fatalities are due to the physical effects of the drug, there have also been reports of death due to self-harm and suicide under the influence of the substance.

### Neurotoxic and cardiotoxic actions

Many of the NBOMe compounds have high potency agonist activity at additional 5-HT receptors and prolonged activation of 5-HT$_{2B}$ can cause cardiac valvulopathy in high doses and chronic use. 5-HT$_{2B}$ receptors have been strongly implicated in causing drug-induced valvular heart disease. The high affinity of NBOMe compounds for adrenergic α$_1$ receptor has been reported to contribute to the stimulant-type cardiovascular effects.
In vitro studies, 25C-NBOMe has been shown to exhibit cytotoxicity on neuronal cell lines SH-SY5Y, PC12, and SN471, and the compound was more potent than methamphetamine at reducing the visibility of the respective cells; the neurotoxicity of the compound involves activation of MAPK/ERK cascade and inhibition of Akt/PKB signaling pathway. 25C-NBOMe, including the other derivative 25D-NBOMe, reduced the visibility of cardiomyocytes H9c2 cells, and both substances downregulated expression level of p21 (CDC24/RAC)-activated kinase 1 (PAK1), an enzyme with documented cardiac protective effects.

### Emergency treatment
## Legality
### Sweden

The Riksdag added 25H-NBOMe to Narcotic Drugs Punishments Act under swedish schedule I ("substances, plant materials and fungi which normally do not have medical use") as of August 1, 2013, published by Medical Products Agency (MPA) in regulation LVFS 2013:15 listed as 25H-NBOMe, and 2-(2,5-dimetoxifenyl)-N-(2-metoxibensyl)etanamin.

### United Kingdom

This substance is a Class A drug in the United Kingdom as a result of the N-benzylphenethylamine catch-all clause in the Misuse of Drugs Act 1971.