Summary
Flavonoids is tracked by OSMF as an investigational option for Long COVID; no regulator has approved it for this indication, and most post-viral conditions have no approved disease-modifying therapy at all. ClinicalTrials.gov lists 1 registered trial linking Flavonoids to Long COVID: 1 has completed. None of the registered studies carries a drug-development phase label, which is typical for behavioural, device and supplement protocols. It plans or enrolled 46 participants. Registered activity dates to 2023. The literature layer holds 9 publications for this pair: 9 other publications. Items here are search-derived or curated references rather than classified trial reports; treat them as leads to read, not as graded evidence.
Long COVID / PASC is tracked on the OSMF post-viral programme alongside ME/CFS, Long COVID, POTS and MCAS. Across the programme, 423 candidate agents are logged for Long COVID, most of them preliminary; this page isolates the record for one of them.
Evidence table
| Evidence tier | C · Preliminary |
|---|---|
| Evidence score | 16.5 (trials 2.5, literature 9.0, tier 5, approved bonus 0.0) |
| Registered trials | 1 total: 0 recruiting, 0 active / not yet recruiting, 1 completed, 0 other |
| Linked publications | 9 (9 other publications) |
| Agent type | Other (Other / Unclassified) |
| Development stage (any indication) | Investigational |
| Mechanism / class | Not recorded |
| Data sources | OSMF therapeutic agent database, ClinicalTrials.gov, PubMed |
How the evidence score is calculated
- Each registered trial scores by status (recruiting / active / enrolling 3, completed 2.5, not yet recruiting 2, unknown 1, terminated / withdrawn / suspended 0.5) plus a phase bonus (phase 3-4 +2, phase 2 +1, phase 1 +0.5). The trial component is capped at 30.
- Each literature item scores by design (Cochrane review 5, meta-analysis 4, systematic review 3, RCT 3, clinical trial publication 2, curated reference 1.5, other PubMed record 1). The literature component is capped at 30.
- The existing evidence tier adds 15 (A / Strong), 10 (B / Moderate), 5 (C / Preliminary) or 0 (D / Anecdotal).
- Agents approved for any indication (max clinical phase 4) add 5, because an approved agent has an established safety profile that lowers the barrier to repurposing trials.
- The score ranks what has been studied, not what works. It does not read effect sizes or directions of effect.
Registered clinical trials
| NCT ID | Title | Status | Phase | Enrolment |
|---|---|---|---|---|
| NCT06064838 | Effects of Cacao Flavonoids in Long COVID-19 Patients (FLALOC) Guillermo Ceballos Reyes · 2023 | completed | Not applicable | 46 |
Published literature
- Review (PubMed validation search) PubMed record PMID 41790576
- Review (PubMed validation search) PubMed record PMID 41415584
- Review (PubMed validation search) PubMed record PMID 38399736
- Review (PubMed validation search) PubMed record PMID 36575843
- Review (PubMed validation search) PubMed record PMID 36141012
- Review (PubMed validation search) PubMed record PMID 35544976
- Review (PubMed validation search) PubMed record PMID 35302260
- Review (PubMed validation search) PubMed record PMID 35028901
- Experimental study (PubMed validation search) PubMed record PMID 40596171
Mechanism and notes
No mechanism of action is recorded for this pair in the source databases.
Clinical notes: Investigational for listed conditions. 1 associated trial(s) and 0 study reference(s) in current data. Review primary sources and consult specialists before use.
Safety: Limited specific safety data in these populations. Review full prescribing information and consult specialist. Many agents used off-label or investigational.
Dosing in studies: See linked studies/trials for reported doses and durations; typical protocols vary widely.
Frequently asked questions
Is Flavonoids approved for Long COVID?
Flavonoids is tracked by OSMF as an investigational option for Long COVID; no regulator has approved it for this indication, and most post-viral conditions have no approved disease-modifying therapy at all. Approval status for the specific indication should always be confirmed with the relevant regulator and prescribing information.
Is Flavonoids in clinical trials for Long COVID?
ClinicalTrials.gov lists 1 registered trial linking Flavonoids to Long COVID: 1 has completed. None of the registered studies carries a drug-development phase label, which is typical for behavioural, device and supplement protocols. It plans or enrolled 46 participants. Registered activity dates to 2023.
What does the evidence show for Flavonoids in Long COVID?
Flavonoids has 1 completed trial and 9 linked publications for Long COVID. Completed trials may or may not have posted results; follow the NCT links to check. OSMF's existing evidence tier for this pair is C (Preliminary), taken from the OSMF therapeutic agent database, which grades agents by the volume and design of condition-specific evidence rather than by effect size.
Cite this page
Data: ClinicalTrials.gov, PubMed, Open Targets, ChEMBL, DGIdb and the OSMF therapeutic agent database. Last updated 2026-10-07. Page built 2026-10-07.