Oleoylethanolamide supplementation improves mood and reduces fatigue in veterans with GWI in a 15-week randomized, double-blind, placebo-controlled exploratory clinical trial

L Laila Abdullah A Andrew P. Keegan M Michael Hoffmann J James Baraniuk W Wendy Mack K Kimberly Sullivan C Cheryl Luis C Cheryl Rindfleisch C Claire J.C. Huguenard A Adam Cseresznye G Gregory J. Aldrich J James E. Evans (Environmental Molecular Sciences Division, Pacific Northwest National Laboratory) D Daniel Paris D Dakota Helgager F Fiona Crawford M Michael Mullan

Abstract

Abstract Gulf War Illness (GWI) affects 32% of Veterans from the 1990–1991 Gulf War. It is characterized by fatigue, mood disturbances, pain and cognitive decrements, with no FDA-approved treatment. This exploratory randomized, double-blind, placebo-controlled trial evaluated the safety and efficacy of oleoylethanolamide (OEA) supplementation in 52 Veterans with GWI (mean age 59 ± 5 SD, 94% males and 79% White). Participants received 200 mg of OEA twice daily or a matching placebo for 10 weeks, followed by a 5-week open-label OEA extension. Outcomes included the Multidimensional Fatigue Inventory (MFI-20), abbreviated Profile of Mood States (POMS), Short-Form McGill Pain Questionnaire, Veterans RAND 36-Item Health Survey (SF-36 V), Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and CNS Vital Signs Test, administered at baseline and 10- and 15-weeks. A main effect of OEA for reducing fatigue (MFI-20, p  ≤ 0.05) and improving the total mood disturbances score (POMS, p  ≤ 0.05) was observed. Participants on OEA reported increased energy, emotional well-being, and social functioning (SF-36 V, p  ≤ 0.05). No changes were seen in cognitive performance or pain. Oleoylethanolamide was well-tolerated with no serious adverse events. In summary, OEA was safe and improved fatigue and mood in Veterans with GWI. Larger trials are needed to confirm these benefits. Registered under ClinicalTrials.gov Identifier no. NCT05252949 (first posted date: 23/02/2022).

Article Details

Volume / Issue Vol. 16, Issue 1
Published January 09, 2026
ISSN 2045-2322
Publisher Nature Portfolio

Journal Info

Scientific Reports

Nature Portfolio

ISSN: 2045-2322 Open Access Life Sciences

Authors (16)

L

Laila Abdullah

A

Andrew P. Keegan

M

Michael Hoffmann

J

James Baraniuk

W

Wendy Mack

K

Kimberly Sullivan

C

Cheryl Luis

C

Cheryl Rindfleisch

C

Claire J.C. Huguenard

A

Adam Cseresznye

G

Gregory J. Aldrich

J

James E. Evans

Environmental Molecular Sciences Division, Pacific Northwest National Laboratory

D

Daniel Paris

D

Dakota Helgager

F

Fiona Crawford

M

Michael Mullan