Nuedexta (AVP-923) is a medicine approved by the U.S. Food and Drug Administration to treat uncontrollable episodes of laughing or crying, a condition known as the pseudobulbar affect. PBA occurs in people with Alzheimer’s disease and other neurological disorders.

Developed by Avanir Pharmaceuticals of Aliso Viejo, California, Nuedexta is also being studied to treat agitation in Alzheimer’s patients.

How Nuedexta works

Nuedexta is a combination of dextromethorphan and quinidine.

Although the exact mechanism by which Nuedexta exerts a therapeutic effect is unclear, scientists believe dextromethorphan blocks certain neuronal pathways that regulate rapid, exaggerated mood swings and related behaviors. This reduces PBA symptoms and agitation. Quinidine helps increase the amount of dextromethorphan available in the blood, enhancing the combo drug’s benefits.

Nuedexta in clinical trials

Researchers assessed Nuedexta’s safety and tolerability in a Phase 3 clinical trial (NCT00056524) to treat PBA associated with multiple neurological conditions, including Alzheimer’s. Results of the study, published in the scientific journal Current Medical Research and Opinion, showed that the treatment caused no serious adverse effects and was well tolerated by all 553 participants.

An open-label, Phase 4 trial (NCT01832350) is now assessing Nuedexta’s safety and efficacy in treating Alzheimer’s patients for PBA. The trial’s primary outcome is reduction of PBA frequency; the secondary outcome is reduction of PBA severity. The study is still ongoing but no longer recruiting patients.

Avanir also studied Nuedexta to treat symptoms of agitation in 194 Alzheimer’s patients in a Phase 2 trial (NCT01584440) that ended in 2014. That study evaluated Nuedexta’s safety, tolerability and efficacy compared to placebo.

The results of that study appeared in the The Journal of the American Medical Association. Among other things, Nuedexta compared to placebo significantly reduced the neuropsychiatric inventory (NPI) agitation/aggression score, which has been used in dementia trials to quantify and qualify changes during a treatment period. Moreover, Nuedexta was generally well tolerated, with only mild adverse events like diarrhea, falls and urinary tract infection.

Other details

Nuedexta’s most common side effects are diarrhea, dizziness, cough, vomiting, weakness and swelling of feet and ankles.


Note: Alzheimer’s News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.