Multivitamin side effects: what 49,761 FDA adverse event reports show
Drug class
Vitamin D, Vitamin C
Brand names
Prenatol-M
Who reports
49,761 reports · 48% serious · 2,330 with death outcome · 66% female
Used for
Prenatol-M™ Indications and Usage: Prenatol-M™ is indicated to provide vitamins and minerals to women throughout pregnancy and during the postnatal period for both lactating and non-lactating mothers, and throughout the childbearing years. Prenatol-M™ may be beneficial in improving the nutritional status of women prior to conception.
What it is
DESCRIPTION: Each caplet contains: Vitamin A (as Retinyl Acetate) ………………....… 1500 mcg RAE Vitamin C (as Ascorbic Acid) ………………….………… 120 mg Vitamin D3 (as Cholecalciferol).……………....... 20 mcg (800 IU) Vitamin E (as Dl-Alpha Tocopheryl Acetate) ….......….….
Boxed warning
None in the current label
Causality screen of the 40 strongest signals
What the badges mean
- Likely indication confounding The term appears in the label's indications: reports probably describe the disease being treated (or its progression), not a drug effect. Classic confounding by indication.
- Reporting / coding artifact An administrative, monitoring or exposure term (product issue, off-label use, 'test normal', overdose...). Not a biological reaction; a high PRR here reflects how reports are coded.
- Lab value / disease marker A laboratory result, investigation or disease-activity marker (antibody positive, CRP abnormal, swollen joint count) not described in the label. These usually mirror the monitored disease or testing protocol rather than a drug effect; not screened further.
- Not in label — unassessed Not found in the label text, not an artifact pattern. This is a genuine candidate for a formal causality assessment (Bradford Hill / WHO-UMC); it has NOT had one here.
Strongest disproportionality signals
Flagged terms (PRR ≥ 2, χ² ≥ 4, n ≥ 10), ranked by PRR; infinite PRRs (no comparator reports) excluded. The EBGM column is a second, shrinkage-based estimate (MGPS) with its 5th percentile EB05 and the BCPNN IC025; a pair flagged by PRR alone is marked PRR-only and should be read as fragile. The strata column recomputes the PRR on serious reports only (and, for the 300 most-reported drugs, adjusted for age band), and flags pairs whose reports are unusually skewed by sex or come mostly from consumers. Each row also shows the PRR against the other drugs of the same FDA class, which removes most confounding by the condition being treated, and a calibrated p-value: on validation, known non-causes average an ROR of about 2, so significance is judged against that empirical null (✓ = p < 0.05 after calibration). 1,123 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Muscle cramp | 52 | 12.5 9.5–16.5ROR 12.5 · calibrated p 0.016 ✓ | 11.9 EB05 9.3 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | ♀ 100% (drug 66%) | not reported in cached trials |
| Haemorrhagic anaemia | 99 | 9.5 7.8–11.6ROR 9.6 · calibrated p 0.039 ✓ | 9.1 EB05 7.7 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious n=99 · 90% consumer | not reported in cached trials |
| Nephrogenic anaemia | 95 | 8.7 7.1–10.7ROR 8.7 · calibrated p 0.053 | 8.3 EB05 7.0 · IC025 +2.7 3/3 methods agree | Not in label — unassessed | serious n=95 | not reported in cached trials |
| Blood testosterone decreased | 117 | 7.2 6.0–8.7ROR 7.3 · calibrated p 0.091 | 7.0 EB05 6.0 · IC025 +2.5 3/3 methods agree | Lab value / disease marker | serious n=23 · ♀ 0% (drug 66%) · 87% consumer | not reported in cached trials |
| Hyperparathyroidism secondary | 42 | 7.1 5.2–9.6ROR 7.1 · calibrated p 0.102 | 6.6 EB05 5.0 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious n=42 | not reported in cached trials |
| Injection site papule | 67 | 6.3 5.0–8.0ROR 6.3 · calibrated p 0.136 | 6.0 EB05 4.9 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | ♀ 100% (drug 66%) · 100% consumer | not reported in cached trials |
| Rebound acid hypersecretion | 41 | 5.7 4.2–7.8ROR 5.7 · calibrated p 0.181 | 5.3 EB05 4.1 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious n=40 | not reported in cached trials |
| Lower gastrointestinal haemorrhage | 93 | 5.3 4.3–6.5ROR 5.3 · calibrated p 0.205 | 5.2 EB05 4.3 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 6.2 · 74% consumer | not reported in cached trials |
| Pre-existing condition improved | 77 | 5.2 4.1–6.5ROR 5.2 · calibrated p 0.219 | 5.0 EB05 4.1 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious n=19 | not reported in cached trials |
| Spinal column stenosis | 56 | 5.0 3.8–6.5ROR 5.0 · calibrated p 0.244 | 4.7 EB05 3.8 · IC025 +1.8 3/3 methods agree | Not in label — unassessed | serious n=50 | not reported in cached trials |
| Wound complication | 40 | 4.9 3.6–6.8ROR 4.9 · calibrated p 0.251 | 4.6 EB05 3.6 · IC025 +1.7 3/3 methods agree | Reporting / coding artifact | serious n=24 · 70% consumer | not reported in cached trials |
| Body height decreased | 123 | 4.8 4.1–5.8ROR 4.8 · calibrated p 0.255 | 4.7 EB05 4.1 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious n=68 | not reported in cached trials |
| Vitamin d decreased | 96 | 4.8 3.9–5.8ROR 4.8 · calibrated p 0.265 | 4.6 EB05 3.9 · IC025 +1.9 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious n=39 · 76% consumer | not reported in cached trials |
| Difficulty in walking | 37 | 4.5 3.3–6.2ROR 4.5 · calibrated p 0.308 | 4.2 EB05 3.2 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious n=24 · ♀ 100% (drug 66%) | not reported in cached trials |
| Thrombophlebitis superficial | 32 | 4.4 3.1–6.3ROR 4.4 · calibrated p 0.323 | 4.1 EB05 3.1 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious n=32 · ♀ 100% (drug 66%) | not reported in cached trials |
| Endometriosis | 49 | 4.4 3.3–5.8ROR 4.4 · calibrated p 0.325 | 4.2 EB05 3.3 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious n=37 · ♀ 100% (drug 66%) · 70% consumer | not reported in cached trials |
| Weight bearing difficulty | 26 | 4.1 2.8–6.0ROR 4.1 · calibrated p 0.379 | 3.8 EB05 2.7 · IC025 +1.3 3/3 methods agree | Not in label — unassessed | serious n=19 · ♀ 100% (drug 66%) | not reported in cached trials |
| Tendon pain | 72 | 4.0 3.2–5.1ROR 4.0 · calibrated p 0.377 | 3.9 EB05 3.2 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious n=52 · 100% consumer | not reported in cached trials |
| Therapy cessation | 479 | 4.0 3.6–4.4ROR 4.0 · calibrated p 0.377 | 3.9 EB05 3.6 · IC025 +1.8 3/3 methods agree | Reporting / coding artifact | serious PRR 5.6 · 73% consumer | not reported in cached trials |
| Initial insomnia | 94 | 3.9 3.2–4.8ROR 3.9 · calibrated p 0.398 | 3.8 EB05 3.2 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious n=23 · 79% consumer | not reported in cached trials |
| Product substitution issue | 524 | 3.9 3.5–4.2ROR 3.9 · calibrated p 0.399 | 3.8 EB05 3.6 · IC025 +1.8 3/3 methods agree | Reporting / coding artifact | serious PRR 5.6 · 95% consumer | not reported in cached trials |
| Intentional device misuse | 40 | 3.8 2.8–5.2ROR 3.8 · calibrated p 0.426 | 3.6 EB05 2.8 · IC025 +1.3 3/3 methods agree | Reporting / coding artifact | ♀ 100% (drug 66%) · 100% consumer | not reported in cached trials |
| Blood calcium increased | 77 | 3.7 3.0–4.7ROR 3.7 · calibrated p 0.439 | 3.6 EB05 3.0 · IC025 +1.5 3/3 methods agree | Lab value / disease marker | serious n=29 · ♀ 100% (drug 66%) · 73% consumer | not reported in cached trials |
| Walking aid user | 58 | 3.7 2.9–4.8ROR 3.7 · calibrated p 0.442 | 3.6 EB05 2.9 · IC025 +1.4 3/3 methods agree | Not in label — unassessed | serious n=32 · 81% consumer | not reported in cached trials |
| Faecal incontinence | 42 | 3.7 2.7–4.9ROR 3.7 · calibrated p 0.458 | 3.5 EB05 2.7 · IC025 +1.3 3/3 methods agree | Not in label — unassessed | serious n=28 | not reported in cached trials |
| Acne cystic | 26 | 3.6 2.5–5.4ROR 3.6 · calibrated p 0.466 | 3.4 EB05 2.5 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | ♀ 100% (drug 66%) · 100% consumer | not reported in cached trials |
| Pharyngolaryngeal pain | 46 | 3.6 2.7–4.8ROR 3.6 · calibrated p 0.465 | 3.5 EB05 2.7 · IC025 +1.3 3/3 methods agree | Not in label — unassessed | serious n=20 · ♀ 100% (drug 66%) | not reported in cached trials |
| Muscle fatigue | 36 | 3.6 2.6–5.0ROR 3.6 · calibrated p 0.469 | 3.5 EB05 2.6 · IC025 +1.2 3/3 methods agree | Not in label — unassessed | – | not reported in cached trials |
| Hangover | 30 | 3.6 2.5–5.1ROR 3.6 · calibrated p 0.475 | 3.4 EB05 2.5 · IC025 +1.2 3/3 methods agree | Not in label — unassessed | – | not reported in cached trials |
| Meniscus injury | 52 | 3.6 2.7–4.7ROR 3.6 · calibrated p 0.473 | 3.5 EB05 2.7 · IC025 +1.3 3/3 methods agree | Not in label — unassessed | serious n=40 | not reported in cached trials |
| Sinus headache | 50 | 3.5 2.7–4.7ROR 3.5 · calibrated p 0.481 | 3.4 EB05 2.7 · IC025 +1.3 3/3 methods agree | Not in label — unassessed | – | not reported in cached trials |
| Local swelling | 145 | 3.5 3.0–4.1ROR 3.5 · calibrated p 0.492 | 3.4 EB05 3.0 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 2.9 · 78% consumer | not reported in cached trials |
| Abdominal adhesions | 26 | 3.5 2.4–5.1ROR 3.5 · calibrated p 0.506 | 3.3 EB05 2.4 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | serious n=24 | not reported in cached trials |
| Pelvic pain | 149 | 3.5 3.0–4.1ROR 3.5 · calibrated p 0.492 | 3.4 EB05 3.0 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 3.4 · ♀ 100% (drug 66%) · 75% consumer | not reported in cached trials |
| Dysmenorrhoea | 107 | 3.5 2.9–4.2ROR 3.5 · calibrated p 0.495 | 3.4 EB05 2.9 · IC025 +1.4 3/3 methods agree | Not in label — unassessed | ♀ 100% (drug 66%) · 100% consumer | not reported in cached trials |
| Laceration | 77 | 3.4 2.7–4.3ROR 3.4 · calibrated p 0.508 | 3.3 EB05 2.8 · IC025 +1.4 3/3 methods agree | Not in label — unassessed | serious n=55 | not reported in cached trials |
| Increased tendency to bruise | 74 | 3.4 2.7–4.3ROR 3.4 · calibrated p 0.514 | 3.3 EB05 2.7 · IC025 +1.3 3/3 methods agree | Not in label — unassessed | serious n=38 | not reported in cached trials |
| Protein total decreased | 30 | 3.4 2.4–4.8ROR 3.4 · calibrated p 0.528 | 3.2 EB05 2.4 · IC025 +1.1 3/3 methods agree | Lab value / disease marker | serious n=28 · 100% clinician | not reported in cached trials |
| Plasma cell myeloma recurrent | 26 | 3.4 2.3–5.0ROR 3.4 · calibrated p 0.532 | 3.2 EB05 2.3 · IC025 +1.0 3/3 methods agree | Not in label — unassessed | 100% clinician | not reported in cached trials |
| Attention deficit/hyperactivity disorder | 26 | 3.4 2.3–5.0ROR 3.4 · calibrated p 0.533 | 3.2 EB05 2.3 · IC025 +1.0 3/3 methods agree | Not in label — unassessed | – | not reported in cached trials |
Trial evidence (ClinicalTrials.gov)
✓ Trial adverse-event data found on ClinicalTrials.gov
Largest completed trials with posted results that list Multivitamin as a study intervention. The right-hand column of the signal table shows whether each FAERS term was also recorded in these trials, with a real denominator (0 of 40 signal terms matched).
- NCT02422745 — COcoa Supplement and Multivitamin Outcomes Study (N=21442, PHASE4; 34 AE terms posted; arms: Active Cocoa Extract; Placebo Cocoa Extract; Active Multivitamin; Placebo Multivitamin)
- NCT00064753 — Folic Acid for Vascular Outcome Reduction In Transplantation (FAVORIT) (N=4110, PHASE2, PHASE3; 1 AE terms posted; arms: High Dose Multivitamin; Low Dose Multivitamin)
Caveats: trial populations, doses and follow-up differ from the reporting population; AE terms are sponsor-coded and matched here by wording; absence from a trial list means the term was not reported above the sponsor's frequency threshold, not that it cannot occur.
Most frequently reported reactions
By raw co-report count, regardless of disproportionality. Common terms here are often the illness itself or generic outcomes.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Fatigue (tiredness) | 3,690 | 2.0 1.9–2.1ROR 2.1 · calibrated p 0.991 | 2.0 EB05 1.9 · IC025 +0.9 | Not in label — unassessed | serious PRR 2.0 | NCT02422745: 3155/5,363 (58.8%) on Multivitamin; 6228/10,723 (58.1%) control |
| Nausea | 3,248 | 1.7 1.7–1.8ROR 1.8 · calibrated p 0.824 | 1.7 EB05 1.7 · IC025 +0.7 | Labeled adverse reaction exact term | serious PRR 1.9 | NCT02422745: 1906/5,363 (35.5%) on Multivitamin; 3756/10,723 (35.0%) control |
| Drug ineffective (drug did not work) | 3,158 | 1.0 1.0–1.0ROR 1.0 · calibrated p 0.314 | 1.0 EB05 1.0 · IC025 -0.0 PRR-only: not supported by EBGM or IC | Reporting / coding artifact | serious PRR 1.0 · 78% consumer | not reported in cached trials |
| Diarrhoea (diarrhea) | 2,824 | 1.9 1.8–1.9ROR 1.9 · calibrated p 0.891 | 1.8 EB05 1.8 · IC025 +0.8 | Labeled adverse reaction exact term | serious PRR 1.9 | NCT02422745: 2880/5,363 (53.7%) on Multivitamin; 5639/10,723 (52.6%) control |
| Headache | 2,609 | 1.8 1.7–1.8ROR 1.8 · calibrated p 0.830 | 1.8 EB05 1.7 · IC025 +0.7 | Not in label — unassessed | serious PRR 1.8 | NCT02422745: 2118/5,363 (39.5%) on Multivitamin; 4176/10,723 (38.9%) control |
| Dizziness | 2,307 | 2.0 1.9–2.0ROR 2.0 · calibrated p 0.946 | 2.0 EB05 1.9 · IC025 +0.9 | Not in label — unassessed | serious PRR 2.1 | NCT02422745: 2091/5,363 (39.0%) on Multivitamin; 4129/10,723 (38.5%) control |
| Dyspnoea (shortness of breath) | 2,047 | 1.5 1.5–1.6ROR 1.5 · calibrated p 0.674 | 1.5 EB05 1.5 · IC025 +0.5 | Not in label — unassessed | serious PRR 1.7 | not reported in cached trials |
| Pain | 1,938 | 1.3 1.3–1.4ROR 1.3 · calibrated p 0.536 | 1.3 EB05 1.3 · IC025 +0.3 | Not in label — unassessed | serious PRR 1.4 | NCT02422745: 2557/5,363 (47.7%) on Multivitamin; 4984/10,723 (46.5%) control |
| Asthenia (weakness) | 1,849 | 2.1 2.0–2.2ROR 2.1 · calibrated p 0.993 | 2.1 EB05 2.0 · IC025 +1.0 | Not in label — unassessed | serious PRR 2.1 | not reported in cached trials |
| Fall | 1,749 | 2.2 2.1–2.3ROR 2.3 · calibrated p 0.918 | 2.2 EB05 2.1 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | serious PRR 2.3 | NCT02422745: 3065/5,363 (57.2%) on Multivitamin; 6059/10,723 (56.5%) control |
| Arthralgia (joint pain) | 1,740 | 1.8 1.7–1.9ROR 1.8 · calibrated p 0.830 | 1.8 EB05 1.7 · IC025 +0.7 | Not in label — unassessed | serious PRR 1.9 · 71% consumer | not reported in cached trials |
| Rash | 1,479 | 1.4 1.4–1.5ROR 1.5 · calibrated p 0.610 | 1.4 EB05 1.4 · IC025 +0.4 | Not in label — unassessed | serious PRR 1.5 | NCT02422745: 1736/5,363 (32.4%) on Multivitamin; 3476/10,723 (32.4%) control |
| Vomiting | 1,471 | 1.3 1.3–1.4ROR 1.3 · calibrated p 0.530 | 1.3 EB05 1.3 · IC025 +0.3 | Not in label — unassessed | serious PRR 1.5 | not reported in cached trials |
| Injection site pain (pain where injected) | 1,463 | 2.0 1.9–2.1ROR 2.1 · calibrated p 0.980 | 2.0 EB05 1.9 · IC025 +0.9 | Not in label — unassessed | serious PRR 2.2 · 85% consumer | NCT02422745: 2557/5,363 (47.7%) on Multivitamin; 4984/10,723 (46.5%) control |
| Insomnia (trouble sleeping) | 1,430 | 2.3 2.2–2.4ROR 2.3 · calibrated p 0.901 | 2.3 EB05 2.2 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | serious PRR 2.1 · 75% consumer | not reported in cached trials |
Unlabeled candidate signals
These flagged terms were not found in the FDA label text and do not match an artifact pattern. They are the pairs that would merit a structured assessment (temporality, dose-response, biological plausibility, consistency across databases, trial or cohort evidence). The screen has not done that; string-matching misses label wording, and a strong PRR can still be stimulated reporting, co-medication, or the disease itself.
- Muscle cramp — n=52, PRR 12.5
- Haemorrhagic anaemia — n=99, PRR 9.5
- Nephrogenic anaemia — n=95, PRR 8.7
- Hyperparathyroidism secondary — n=42, PRR 7.1
- Injection site papule — n=67, PRR 6.3
- Rebound acid hypersecretion — n=41, PRR 5.7
- Lower gastrointestinal haemorrhage — n=93, PRR 5.3
- Pre-existing condition improved — n=77, PRR 5.2
- Spinal column stenosis — n=56, PRR 5.0
- Body height decreased — n=123, PRR 4.8
Want to assess one of these properly? The runbook describes the Bradford Hill / trial-evidence workflow used on the assessment page, and handoff_top1000_signals.csv lists the strongest unassessed pairs across all drugs.
Common questions
What are the most reported side effects of Multivitamin?
In FDA FAERS, the most frequently co-reported reaction terms for Multivitamin are fatigue, nausea, diarrhoea, headache, dizziness, dyspnoea. These are report counts, not rates: FAERS has no denominator, reporting is voluntary and uneven, and a term can be reported because of the illness being treated rather than the drug.
Does Multivitamin have an FDA boxed warning?
No. The FDA label retrieved for Multivitamin has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Multivitamin causes these side effects?
No. A disproportionality signal (PRR, ROR) means a reaction is reported more often with this drug than with others in the database. That can reflect a real effect, but also the disease being treated, stimulated reporting after news or litigation, co-medications, or how reports are coded. Causality needs temporality, dose-response, biological plausibility, consistency across data sources and, ideally, trial or cohort evidence. This page screens each term against the FDA label and ClinicalTrials.gov results; it does not establish causation.
Sources & methods
- FDA label via openFDA (set ID 17559a44-94b7-9ca0-e063-6294a90a2123, effective 20240506; matched on
openfda.generic_name.exact:"MULTIVITAMIN") - Bayesian shrinkage measures computed offline over all 1,317,300 cached pairs: BCPNN information component (IC, with Norén closed-form IC025) and MGPS empirical-Bayes geometric mean (EBGM, EB05) with a two-component gamma prior fitted by maximum marginal likelihood (α₁=0.57, β₁=0.02, α₂=1.42, β₂=0.70, w=0.17); unstratified
- FAERS pair statistics from the OpenPV build of 2026-09-14 (openFDA
count=aggregation, fieldpatient.drug.openfda.generic_name.exact, 1,163 reaction terms, min 3 co-reports); PRR/ROR with 95% CI, chi-square with Yates correction - Serious-only and stratified counts (serious:1, patient.patientsex, primarysource.qualification) from openFDA count queries; serious-only PRR uses the drug serious report total and the term global serious total (N_serious=11,882,979); strata shown only when n ≥ 20
- Seriousness and sex counts from openFDA
count=serious,patient.patientsex,seriousnessdeath - ClinicalTrials.gov API v2 (query
MULTIVITAMIN, results-bearing studies sorted by enrollment)
Page generated 2026-10-14. Label and PubChem text are retrieved automatically and may lag the current label; always check the current prescribing information. OpenPV is a beta research tool of the Open Source Medicine Foundation.