What Is Hesperidin?
Hesperidin is a citrus bioflavonoid found in the peel and pulp of oranges, lemons, and other citrus fruits. Standardised hesperidin extracts (often 80‑90 % purity) are available as capsules or powders. Long used for vascular health and venous insufficiency, hesperidin has antiviral, anti‑inflammatory, antioxidant, and endothelial‑protective properties that make it a promising candidate for managing Long COVID symptoms such as fatigue, brain fog, and exercise intolerance.
How Hesperidin May Help for Long COVID
Blocks Viral Entry & Replication – Cell studies show hesperidin binds the SARS‑CoV‑2 spike and main protease (3CLpro), potentially reducing lingering viral load.
Calms Inflammation – Hesperidin lowers inflammatory cytokines and oxidative stress, addressing the chronic inflammation seen in Long COVID.
Supports Blood Vessels & Microcirculation – It boosts endothelial nitric‑oxide production, improves flow‑mediated dilation, and may counter the microclots implicated in Long COVID.
Neuroprotective & Antioxidant – A product of hesperidin, hesperetin, crosses the blood–brain barrier, where it reduces neuro‑inflammation and supports cognitive function.
What the Research Says
Human studies directly testing hesperidin in Long COVID are limited, but early clinical trials and mechanistic research suggest several potential benefits. These include reductions in inflammation, support for endothelial function, and antiviral effects that may be relevant for managing persistent symptoms such as fatigue, brain fog, and post-exertional malaise. Hesperidin has shown promising results in acute COVID-19 trials, and preliminary findings in Long COVID populations support further investigation.
Key studies on Melatonin and Long COVID
Studies Showing Positive Results
This study used a lime/citrus extract rich in hesperidin (4.5 g/day for 7 days) in 66 Long COVID patients at least one month post-infection. It found a greater drop in total symptom scores compared to placebo and reduced risk of fatigue and post-exertional malaise by 65–75%. Only mild GI discomfort was reported, which resolved after treatment.
This study gave 1 g/day of hesperidin for 14 days to 216 outpatients with acute COVID-19. It found that hesperidin shortened the persistence of key symptoms (fever, cough, shortness of breath, anosmia) by day 14 in sensitivity analysis (36% vs 51% symptomatic). The treatment was well tolerated with no drug-related serious adverse events.
Theoretical Support
This article summarises hesperidin’s binding affinity to SARS‑CoV‑2 targets, endothelial benefits, and antioxidant effects.
This article explains how Hesperidin improves endothelial nitric oxide (NO) production, reduces oxidative stress, and supports blood flow.
Final Thoughts and Typical Use
Hesperidin is an accessible, citrus‑derived compound that shows early promise for reducing lingering symptoms of COVID‑19. Its multi‑target action – antiviral, anti‑inflammatory, endothelial‑support – aligns well with the leading theories of Long COVID pathology. Typical dosing is around 500-1000 mg per day of ~90% hesperidin powder. While larger dedicated trials are needed, hesperidin’s strong safety record makes it a reasonable, low‑risk option to discuss with your clinician.