A lesser-known novel dissociative substance of the diarylethylamine class that produces dissociative and hallucinogenic effects when administered. It is structurally related to methoxphenidine as well as ephenidine.
The synthesis of diphenidine was first reported in 1924. Shortly after the 2013 UK arylcyclohexylamine ban, diphenidine and the related compound methoxphenidine became available on the grey market. In 2014, two cases of diphenidine sold in combination with synthetic cannabinoids in Japanese herbal incense blends, one of which implicated in a fatal overdose.
Diphenidine is classified as an NMDA receptor antagonist. Members of this class induce a state known as “dissociative anesthesia” and are used in both medical and recreational contexts. These include arylcyclohexylamines like ketamine and phencyclidine (PCP), as well as dextromethorphan (DXM).
Anecdotal reports describe high doses of diphenidine producing “bizarre somatosensory phenomena and transient anterograde amnesia.”
Not however known to have an affinity for the opioid receptors.
Very little data exists about the pharmacological properties, metabolism, and toxicity of diphenidine in humans, and it has an extremely limited history of human usage. Many reports suggest that it may pose different risks than traditional dissociatives. Also highly advised to use harm reduction practices if using this substance.