How Do Otic NMDA Antagonists Work?

Otic NMDA antagonists are medications that suppress the hyperactivity of excited nerve cells (neurons) in the auditory nerve. Currently, the first otic NMDA antagonist is in clinical trials for safety and efficacy for the treatment of acute inner ear tinnitus (ringing in the ear).

N-methyl-D-aspartate (NMDA) antagonists block the NMDA receptors on neurons from being stimulated by glutamate and aspartate. Glutamate and aspartate are excitatory chemical messengers (neurotransmitters) that neurons release after an injury or infection.

Damage to the sensory nerves in the ear is thought to cause the release of glutamate and aspartate, resulting in spontaneous firing of auditory neurons. The abnormal hyperactivity of the neurons is perceived as tinnitus.

Information on dosage and administration of NMDA antagonists is not available at present. The first otic NMDA antagonist is in clinical trial pending approval for treatment of acute inner ear tinnitus following acute acoustic trauma or otitis media (middle ear infection and inflammation).

Information on side effects of otic NMDA antagonists are not fully available but may include the following:

• Transient increase in tinnitus loudness
• Muffled hearing

Information contained herein is not intended to cover all possible side effects, precautions, warnings, drug interactions, allergic reactions, or adverse effects. Check with your doctor or pharmacist to make sure these drugs do not cause any harm when you take them along with other medicines. Never stop taking your medication and never change your dose or frequency without consulting your doctor.

The generic and brand name of the first otic NMDA antagonist drug pending FDA approval is:

• Esketamine otic (Keyzilen)