In a consequential development for post-viral medical research, a large-scale United Kingdom clinical trial has revealed that repurposed over-the-counter antihistamines and prescription anti-inflammatory drugs offer modest, albeit transient, benefits in mitigating Long COVID fatigue. The findings, published in The Lancet Infectious Diseases in July 2026, provide critical empirical data for the millions of patients grappling with post-acute sequelae of SARS-CoV-2 infection.

The meticulous Trial Design

Funded by the National Institute for Health and Care Research (NIHR) and led by researchers at UCL and UCLH, the multisite, open-label, randomised controlled trial involved nearly 800 adults in England. Participants were randomly assigned to receive either usual specialist supportive care alone, or usual care combined with one of three repurposed medications: a combination of antihistamines (famotidine and loratadine), the anti-inflammatory drug colchicine, or the anticoagulant rivaroxaban, administered over a 12-week period.

Transient amelioration of Symptoms

The research team documented that all cohorts experienced a meaningful reduction in self-reported fatigue over the initial 12 weeks, improving by an average of 4.3 points on a 40-point scale. This baseline improvement underscores the inherent value of specialist Long COVID clinical care. However, those receiving antihistamines and colchicine demonstrated a small, additional benefit—an extra 1.5 point improvement. Crucially, this marginal advantage was not sustained at the 24-week mark, twelve weeks after participants ceased the pharmacological intervention, indicating the effects were strictly contingent upon active administration.

Implications for ME/CFS

Dr. Charles Shepherd, Honorary Medical Adviser to the ME Association, noted that these findings hold potential relevance for Myalgic Encephalomyelitis (ME/CFS), as both allergic pathways and systemic inflammation are heavily implicated in its pathophysiology. Nevertheless, he cautioned against self-medication, emphasizing that no proper clinical trials have yet validated these specific drug regimens for ME/CFS, and that rivaroxaban demonstrated no discernible benefit whatsoever in this Long COVID cohort.

Official Institutional Communique

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