Single-active oral pantothenic acid exposure and diarrhea risk
conclusionDiarrhea has been reported after high-dose oral single-product exposure, warranting Caution. The excess risk versus placebo, incidence in general users and minimum harmful dose remain unverified.
boundaryReused NIH S06 cites 10 g/day as an example of very high intake with possible mild diarrhea and GI distress. Exact case count, denominator, salt and duration were not verified in that extraction. The example is not a toxicity threshold, upper limit, dosing recommendation or newly verified event rate. SCF and CIR assessments summarize historical reports including occasional diarrhea at 10–20 g/day. Original case tables, exact formulation, duration and comparator denominators were not recovered; later CIR and original assessments were not counted as independent replications. Cosmetic-use safety conclusions were not converted into oral safety authorization. The US FNB 1998 assessment described insufficient adverse-effect reports to derive an upper limit. The inspected EFSA version 11 (2025-08) table also indicates inadequate data to derive a pantothenic acid upper limit. This is not unlimited safety or a legally permitted treatment dose.
Four separate assessment dimensions
| Effect direction and size | Diarrhea has been reported after high-dose oral single-product exposure, warranting Caution. The excess risk versus placebo, incidence in general users and minimum harmful dose remain unverified. |
|---|---|
| Evidence certainty | A diarrhea signal follows high-dose oral single-product exposure, while excess risk versus placebo, population incidence and the minimum harmful dose remain unverified. |
| Applicability | New or worsened diarrhea in adults exposed to single-active oral pantothenic acid. Direct data are in healthy adults aged 18–55; other formulations and populations are not pooled. |
| Safety | The adverse-event signal is retained without turning small uncontrolled study counts into incidence, a risk ratio or a safe threshold. Direct risks in pregnancy, lactation, children, liver/kidney disease and long exposure are unverified. Study doses and nutrition references are not personal dosing instructions. |
Because this is a safety question, the A-F efficacy grade and numeric efficacy score do not apply. Document quality B is not a hazard grade or probability.
Useful facts when choosing a product
- The directly studied preparation was a pantothenic acid tablet (as D-calcium pantothenate). Events from pantethine, pantetheine, dexpanthenol/panthenol, B-complex products or multivitamins are not attributed to it. Manufacturing origin, batch, purity, excipients and equivalent risks of other salts are unverified.
- The tablet is labeled pantothenic acid 500 mg (as D-calcium pantothenate), while the dosing table says calcium pantothenate. The pharmacokinetic section mentions 550 mg calcium salt versus 500 mg described as free base. Because the clinical-dose acid/salt basis is unclear, actual salt, acid and cumulative masses were not converted.
- Follow-up extended to Day 9 after single dosing and Day 22 for the 14-day repeated exposure. The fed-repeat washout is 2–3 weeks in the methods and summarized as 2 weeks in the abstract. Sequence and meal differences prevent treating periods as independent randomized groups or adding their participant counts.
- Reused NIH S06 cites 10 g/day as an example of very high intake with possible mild diarrhea and GI distress. Exact case count, denominator, salt and duration were not verified in that extraction. The example is not a toxicity threshold, upper limit, dosing recommendation or newly verified event rate.
- The US FNB 1998 assessment described insufficient adverse-effect reports to derive an upper limit. The inspected EFSA version 11 (2025-08) table also indicates inadequate data to derive a pantothenic acid upper limit. This is not unlimited safety or a legally permitted treatment dose.
- The reused US adequate intakes are 5 mg/day for adults, 6 mg/day during pregnancy and 7 mg/day during lactation. Adequate intake concerns nutritional adequacy, not a diarrhea threshold or high-dose treatment instruction. Food intake and high-dose single-product exposure were not pooled.
Chamgap Semantic Classification Code
Permanent code issued
S.pantothenic-acid.oral.diarrhea-adverse-event-risk.increase.unexposed-or-lower-exposureSubstances and nutrients > Pantothenic acid (vitamin B5), sole active ingredient > Oral > Risk of new or worsened diarrhea adverse events > Increase risk > Unexposed or lower exposure
Safety-only claim. General GI distress, abdominal pain, nausea and diarrhea frequency in IBS-D remain separate boundaries. A suitable comparative risk estimate is unverified. The code identifies the intervention and claim; it never contains the evidence grade, score, or safety result.
Exact Claim Classification
These independent facets prevent evidence from different forms, routes, populations, effects, and comparators from being mixed.
| Intervention class | S · Supplement or nutraceutical |
|---|---|
| Canonical ingredient or intervention | Single-active pantothenic acid (vitamin B5); D-calcium pantothenate in direct exposure data is separately identified |
| Source or part used | Oral single-vitamin preparation; manufacturing origin, batch and purity unverified. Food intake is separate context |
| Formulation or processing | Main study: Rugby-distributed pantothenic acid tablets (as D-calcium pantothenate). Release type, excipients and actual acid/salt mass basis unverified |
| Route | Oral; topical and injected routes excluded |
| Dose | Reported doses retained by study: single 500, 1000, 2000, 5000 mg and repeated 2000 mg/day. No acid/salt conversion or toxicity threshold derived |
| Duration | Single exposure and 14-day repeated exposure separated. Main single-dose follow-up to Day 9; repeated-dose follow-up to Day 22. Minimum harmful duration for long-term/high-dose use unverified |
| Population | Adults orally exposed to single-active B5; direct data in healthy adults aged 18–55. Arthritis, pediatric, pregnant, lactating, and liver/kidney-disease groups are not pooled |
| Effect or condition | Risk of new or worsened diarrhea adverse events after single-active oral pantothenic acid exposure |
| Primary endpoint | Diarrhea adverse events; main-study MedDRA 21.0 diarrhea term retained separately from abdominal pain, nausea and composite GI symptoms; new/worsened counts not reported separately |
| Comparator | Unexposed/placebo/lower exposure/other dose preferred, but a suitable comparative diarrhea risk estimate is unverified. Main study is open-label and uncontrolled; fed repeat involves the same participants |
| Duplicate-detection key | S|pantothenic-acid-single-active|oral|adults|new-or-worsened-diarrhea|exposure-stratified|comparator-as-available |
What the research actually shows
Rao studied 40 healthy adults aged 18–55 in a single-center open-label study. The single-dose part had 32 completers and the repeated-dose part 8. Other drugs/supplements were prohibited, but dietary pantothenic acid was not controlled. There was no placebo group or randomized dose allocation.
In Table 6, 1 of 8 participants reported diarrhea after the paper-labeled 5000 mg fasted single dose. In the subsequent fed single-dose condition in the same 8 people, 0 reported it. These are small-study observations by condition, not population incidence, a causal risk ratio, or proof that food prevents diarrhea.
The 500, 1000 and 2000 mg fasted single-dose conditions and the 2000 mg/day 14-day repeated condition each reported 0 diarrhea cases among 8 participants. This reported 0 is a collected table result, not proof of no risk. Nausea, vomiting and abdominal discomfort were separate terms and were not added to diarrhea.
The main study used the MedDRA 21.0 diarrhea term. Stool-frequency/consistency criteria, individual baseline symptoms, separation of new diarrhea from worsening, and diarrhea-specific severity, onset and duration were not reported or not verified. General GI discomfort or loose stool was not recoded as diarrhea.
The main study was funded by CoA Therapeutics. Author employment, consultancy and shareholdings linked to development companies were disclosed. These ties are retained; unverified registration, protocol and statistical analysis plan are not described as proven absence of preregistration.
Comparable unexposed/placebo risks, background diarrhea frequency, minimum harmful dose/duration, individual susceptibility and contributions of excipients, infection or diet are unverified. No risk difference, risk ratio, incidence rate, CI, P value or NNH was derived. Study doses are not personal dosing instructions.
Why the safety label is Warning
The current conclusion is a diarrhea signal after high-dose oral single-product exposure. It does not establish the magnitude of excess risk in general users, that lower doses are risk-free, or that taking it with food prevents diarrhea. Efficacy grades, efficacy scores and a numerical risk score are not applied.
In Table 6, 1 of 8 participants reported diarrhea after the paper-labeled 5000 mg fasted single dose. In the subsequent fed single-dose condition in the same 8 people, 0 reported it. These are small-study observations by condition, not population incidence, a causal risk ratio, or proof that food prevents diarrhea.
Comparable unexposed/placebo risks, background diarrhea frequency, minimum harmful dose/duration, individual susceptibility and contributions of excipients, infection or diet are unverified. No risk difference, risk ratio, incidence rate, CI, P value or NNH was derived. Study doses are not personal dosing instructions.
Counterevidence and limits. The 500, 1000 and 2000 mg fasted single-dose conditions and the 2000 mg/day 14-day repeated condition each reported 0 diarrhea cases among 8 participants. This reported 0 is a collected table result, not proof of no risk. Nausea, vomiting and abdominal discomfort were separate terms and were not added to diarrhea. The arthritis trial summarized by SCF escalated calcium pantothenate over 8 weeks and described no treatment side effects. The narrative total of 94 differs from the group counts of 47 and 46, which sum to 93. Without the primary diarrhea-event table, this was not converted into 0 diarrhea events or a verified safety denominator. Comparable unexposed/placebo risks, background diarrhea frequency, minimum harmful dose/duration, individual susceptibility and contributions of excipients, infection or diet are unverified. No risk difference, risk ratio, incidence rate, CI, P value or NNH was derived. Study doses are not personal dosing instructions.
Review performed and remaining limitations
The directly studied preparation was a pantothenic acid tablet (as D-calcium pantothenate). Events from pantethine, pantetheine, dexpanthenol/panthenol, B-complex products or multivitamins are not attributed to it. Manufacturing origin, batch, purity, excipients and equivalent risks of other salts are unverified. The main study used the MedDRA 21.0 diarrhea term. Stool-frequency/consistency criteria, individual baseline symptoms, separation of new diarrhea from worsening, and diarrhea-specific severity, onset and duration were not reported or not verified. General GI discomfort or loose stool was not recoded as diarrhea. The tablet is labeled pantothenic acid 500 mg (as D-calcium pantothenate), while the dosing table says calcium pantothenate. The pharmacokinetic section mentions 550 mg calcium salt versus 500 mg described as free base. Because the clinical-dose acid/salt basis is unclear, actual salt, acid and cumulative masses were not converted. Follow-up extended to Day 9 after single dosing and Day 22 for the 14-day repeated exposure. The fed-repeat washout is 2–3 weeks in the methods and summarized as 2 weeks in the abstract. Sequence and meal differences prevent treating periods as independent randomized groups or adding their participant counts. The main study was funded by CoA Therapeutics. Author employment, consultancy and shareholdings linked to development companies were disclosed. These ties are retained; unverified registration, protocol and statistical analysis plan are not described as proven absence of preregistration. The main study reported no deaths, serious adverse events or adverse-event discontinuations. This short study in healthy adults does not establish absence of diarrhea risk during long-term use or in pregnancy, lactation, children, older adults or liver/kidney disease. Comparable unexposed/placebo risks, background diarrhea frequency, minimum harmful dose/duration, individual susceptibility and contributions of excipients, infection or diet are unverified. No risk difference, risk ratio, incidence rate, CI, P value or NNH was derived. Study doses are not personal dosing instructions. Review was single-assistant self-review. Primary HTML/PDF tables and official assessments were compared, but registry and some metadata-access failures remain. This is neither independent external review nor assurance that no correction, retraction or unpublished evidence exists. The initial content baseline is 2026-09-15. New comparative safety data, full text, salt/label clarification, corrections, retractions, regulatory changes, or numeric/classification errors trigger dated revisions under the same ID and URL after assignment. An actual server publication date is unassigned.
Search scope and limitations. Executed searches, access and selection records are retained in the transfer package.
Evidence Table
| Study | Design | Sample | Funding | Endpoint | Result | Weight |
|---|---|---|---|---|---|---|
| Rao et al. 2021 | Single-center open-label sequential single-dose cohorts plus a separate multiple-dose cohort | 40 healthy adults; 32 single-dose and 8 repeated-dose completers | Funded by CoA Therapeutics; employment, consultancy and shareholdings disclosed | MedDRA 21.0 diarrhea adverse event | Paper-labeled 5000 mg fasted single dose: 1/8; subsequent fed repeat in the same 8: 0/8. The 500, 1000 and 2000 mg fasted single-dose and 2000 mg/day 14-day conditions each reported 0/8 | Direct signal and descriptive counts; not a randomized placebo risk estimate or population incidence |
| GPRG arthritis trial 1980 | Placebo-controlled double-blind trial summarized by SCF; primary event table unavailable | Narrative total 94, conflicting with 47+46=93 | Unverified | Narrative treatment side effects; diarrhea-specific event table unverified | Secondary summary reported no treatment side effects; not converted to zero diarrhea events | Counter-evidence and context |
| Official and expert high-dose summaries | Official and expert summaries of historical oral observations | Original case denominator unverified | Underlying cases unverified; CIR 2022 supported by CIR/Personal Care Products Council | Diarrhea and GI distress at high doses | A 10 g/day example and historical 10–20 g/day reports; duration, exact formulation and event count unverified | Qualitative high-dose safety signal only; overlapping review lineage not counted as independent replication |
| Evans pantethine trial excluded | Wrong molecule | Not applicable | Unverified | Diarrhea with pantethine | Not attributed to single-active pantothenic acid | Excluded |
| Yang 2014 acne product excluded | Monotherapy composition not established | Not applicable | Unverified | Product-level tolerability | Not transferred to single-active pantothenic acid risk | Excluded |
Receipt — 9 References
Evidence access cutoff: 2026-09-15. Each citation states its actual access level (full-text transcription, abstract, index, or other) and remaining limitations. Bibliographic checking does not certify the study results or treatment efficacy.
Technical integration by: Codex · Evidence date: 2026-09-15 · Corrections: none
Cite this safety assessment
[Chamgap] Single-active oral pantothenic acid exposure and diarrhea risk — Efficacy grade N/A · Safety caution. 9 cited sources checked. Source: https://chamgap.com/en/verdicts/gut/oral-pantothenic-acid-single-active-diarrhea-risk/ · CC BY 4.0What this document does and does not do
Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.