Neramexane
Neramexane is an aminocyclohexane derivative and moderate-affinity, uncompetitive NMDA receptor antagonist, structurally and pharmacologically related to memantine. It was investigated in humans for tinnitus, Alzheimer's disease and other conditions but was not brought to market after mixed trial results.
01 Overview
Neramexane was developed as a follow-on to memantine, sharing its uncompetitive, voltage-dependent NMDA blockade and fast off-rate, which keep it largely free of dissociative effects at studied doses. It also has activity at nicotinic acetylcholine receptors, which was of interest for tinnitus.
Multiple phase II/III trials were run, particularly for subjective tinnitus, but efficacy did not consistently reach endpoints and clinical development was halted. It is therefore an investigational drug with real but limited human data rather than an approved product or a recreational substance.
02 Mechanism
Uncompetitive, voltage-dependent open-channel NMDA receptor antagonist (memantine-like), with additional antagonism at alpha9/alpha10 and other nicotinic acetylcholine receptors.
03 Dosing
| Tier | Dose | Route | Notes |
|---|---|---|---|
| Trial dosing (tinnitus) | 25–75 mg/day | Oral | Doses used in clinical trials; not an approved regimen. |
04 Effects
| Effect | Magnitude | Evidence | |
|---|---|---|---|
| NMDA antagonismMemantine-like glutamatergic dampening studied for tinnitus and cognition. | n/a | Clinical | |
| Tinnitus reduction (investigated)Some trials suggested benefit in subjective tinnitus, but results were not consistent enough for approval. | inconsistent | Clinical |
05 Side effects
| Effect | Severity | Frequency | Evidence | Countermeasures |
|---|---|---|---|---|
| Dizziness and headacheDizziness, headache and nausea reported in trials, generally mild. | Mild | Common | Clinical | |
| Uncertain long-term safetyAs an unapproved investigational agent, long-term human safety is not established. | Moderate | Unknown | Unconfirmed |