Thyroid side effects: what 2,806 FDA adverse event reports show
Drug class
Not stated in label
Who reports
2,806 reports · 47% serious · 118 with death outcome · 85% female
Used for
Thyroid Tablets are indicated: 1. As replacement or supplemental therapy in patients with hypothyroidism of any etiology, except transient hypothyroidism during the recovery phase of subacute thyroiditis. This category includes cretinism, myxedema, and.
What it is
DESCRIPTION Thyroid Tablets USP for oral use are a natural preparation derived from porcine thyroid glands. (T3 liothyronine is approximately four times as potent as T4 levothyroxine on a microgram for microgram basis.) They provide 38 mcg levothyroxine (T4) and 9 mcg liothyronine (T3) per grain of thyroid.
Boxed warning
Drugs with thyroid hormone activity, alone or together with other therapeutic agents, have been used for the treatment of obesity. In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction.
Causality screen of the 40 strongest signals
What the badges mean
- Labeled — boxed warning The term (or its clinical synonym) appears in the FDA boxed warning: causality is regulator-recognised and considered serious.
- 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 flags pairs whose reports are unusually skewed by sex or come mostly from consumers rather than clinicians. 148 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 |
|---|---|---|---|---|---|---|
| Thyroid disorder | 23 | 11.2 7.4–16.8ROR 11.2 · χ² 203 / p 3e-46 | 10.3 EB05 6.9 · IC025 +2.5 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious PRR 14.0 · 82% consumer | no trial data cached |
| Hereditary angioedema | 13 | 9.3 5.4–15.9ROR 9.3 · χ² 88 / p 4e-21 | 7.7 EB05 4.5 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 12.4 | no trial data cached |
| Tooth abscess | 11 | 8.1 4.5–14.5ROR 8.1 · χ² 61 / p 3e-15 | 6.4 EB05 3.7 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 12.9 | no trial data cached |
| Intervertebral disc degeneration | 10 | 8.0 4.3–14.9ROR 8.1 · χ² 55 / p 7e-14 | 6.3 EB05 3.5 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 9.0 | no trial data cached |
| Poor venous access | 11 | 8.0 4.4–14.4ROR 8.0 · χ² 60 / p 4e-15 | 6.3 EB05 3.7 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious n=11 | no trial data cached |
| Blood triglycerides increased | 18 | 7.6 4.8–12.0ROR 7.6 · χ² 97 / p 4e-23 | 6.6 EB05 4.3 · IC025 +1.9 3/3 methods agree | Lab value / disease marker | serious PRR 13.8 | no trial data cached |
| Bladder disorder | 10 | 7.5 4.0–14.0ROR 7.5 · χ² 50 / p 7e-13 | 5.9 EB05 3.3 · IC025 +1.4 3/3 methods agree | Not in label — unassessed | serious n=6 | no trial data cached |
| Synovitis | 15 | 6.2 3.8–10.3ROR 6.2 · χ² 61 / p 4e-15 | 5.3 EB05 3.4 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 8.0 | no trial data cached |
| Fracture | 15 | 5.9 3.6–9.8ROR 5.9 · χ² 57 / p 3e-14 | 5.1 EB05 3.3 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 7.9 | no trial data cached |
| Sleep apnoea syndrome | 15 | 5.9 3.5–9.7ROR 5.9 · χ² 56 / p 4e-14 | 5.0 EB05 3.2 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 8.0 | no trial data cached |
| Head discomfort | 13 | 5.5 3.2–9.5ROR 5.5 · χ² 44 / p 2e-11 | 4.7 EB05 2.9 · IC025 +1.3 3/3 methods agree | Not in label — unassessed | serious PRR 6.5 | no trial data cached |
| Gastroenteritis viral | 13 | 5.4 3.1–9.2ROR 5.4 · χ² 42 / p 5e-11 | 4.6 EB05 2.9 · IC025 +1.3 3/3 methods agree | Not in label — unassessed | serious PRR 11.5 | no trial data cached |
| Heart rate irregular | 16 | 5.3 3.2–8.6ROR 5.3 · χ² 51 / p 4e-13 | 4.6 EB05 3.0 · IC025 +1.4 3/3 methods agree | Not in label — unassessed | serious PRR 5.8 | no trial data cached |
| Bone pain | 41 | 5.2 3.9–7.1ROR 5.3 · χ² 136 / p 9e-32 | 4.9 EB05 3.8 · IC025 +1.8 3/3 methods agree | Not in label — unassessed | serious PRR 8.3 · ♀ 62% (drug 85%) | no trial data cached |
| Osteoarthritis | 29 | 5.1 3.6–7.3ROR 5.1 · χ² 92 / p 5e-22 | 4.7 EB05 3.5 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 6.5 · ♀ 56% (drug 85%) | no trial data cached |
| Blood cholesterol increased | 30 | 4.8 3.4–6.9ROR 4.9 · χ² 87 / p 6e-21 | 4.5 EB05 3.3 · IC025 +1.6 3/3 methods agree | Lab value / disease marker | serious PRR 6.8 | no trial data cached |
| Hypothyroidism | 19 | 4.5 2.8–7.0ROR 4.5 · χ² 48 / p 3e-12 | 4.1 EB05 2.8 · IC025 +1.3 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 5.4 | no trial data cached |
| Tooth disorder | 13 | 4.3 2.5–7.5ROR 4.4 · χ² 30 / p 2e-8 | 3.8 EB05 2.4 · IC025 +1.0 3/3 methods agree | Not in label — unassessed | serious PRR 4.2 | no trial data cached |
| Pain in jaw | 16 | 4.2 2.6–6.9ROR 4.2 · χ² 36 / p 9e-10 | 3.8 EB05 2.5 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | serious PRR 5.2 | no trial data cached |
| Retching | 12 | 4.2 2.4–7.4ROR 4.2 · χ² 26 / p 1e-7 | 3.7 EB05 2.3 · IC025 +0.9 3/3 methods agree | Not in label — unassessed | serious PRR 6.8 | no trial data cached |
| Joint injury | 12 | 4.2 2.4–7.4ROR 4.2 · χ² 26 / p 2e-7 | 3.7 EB05 2.3 · IC025 +0.9 3/3 methods agree | Not in label — unassessed | serious PRR 5.0 | no trial data cached |
| Gallbladder disorder | 10 | 4.2 2.2–7.8ROR 4.2 · χ² 21 / p 2e-6 | 3.6 EB05 2.1 · IC025 +0.8 3/3 methods agree | Not in label — unassessed | serious PRR 5.6 | no trial data cached |
| Sinus disorder | 11 | 4.1 2.3–7.5ROR 4.2 · χ² 23 / p 7e-7 | 3.6 EB05 2.2 · IC025 +0.8 3/3 methods agree | Not in label — unassessed | serious PRR 6.0 | no trial data cached |
| Fibromyalgia | 13 | 4.0 2.3–6.9ROR 4.0 · χ² 26 / p 1e-7 | 3.6 EB05 2.2 · IC025 +0.9 3/3 methods agree | Not in label — unassessed | serious PRR 5.0 | no trial data cached |
| Oral pain | 12 | 4.0 2.3–7.0ROR 4.0 · χ² 24 / p 5e-7 | 3.5 EB05 2.2 · IC025 +0.9 3/3 methods agree | Not in label — unassessed | serious PRR 3.0 | no trial data cached |
| Therapeutic response unexpected | 24 | 4.0 2.7–5.9ROR 4.0 · χ² 51 / p 5e-13 | 3.7 EB05 2.6 · IC025 +1.2 3/3 methods agree | Reporting / coding artifact | serious PRR 8.0 | no trial data cached |
| Eructation (belching) | 10 | 3.9 2.1–7.3ROR 3.9 · χ² 19 / p 6e-6 | 3.4 EB05 2.0 · IC025 +0.7 3/3 methods agree | Not in label — unassessed | serious n=3 | no trial data cached |
| Hypersomnia | 15 | 3.9 2.4–6.5ROR 3.9 · χ² 30 / p 2e-8 | 3.5 EB05 2.3 · IC025 +1.0 3/3 methods agree | Not in label — unassessed | serious PRR 2.9 | no trial data cached |
| Head injury | 16 | 3.8 2.3–6.2ROR 3.8 · χ² 30 / p 2e-8 | 3.5 EB05 2.3 · IC025 +1.0 3/3 methods agree | Not in label — unassessed | serious PRR 5.0 | no trial data cached |
| Gait disturbance | 93 | 3.6 3.0–4.4ROR 3.7 · χ² 175 / p 2e-40 | 3.6 EB05 3.0 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 3.8 · 77% consumer | no trial data cached |
| Pollakiuria (frequent urination) | 20 | 3.6 2.3–5.6ROR 3.6 · χ² 35 / p 2e-9 | 3.4 EB05 2.3 · IC025 +1.0 3/3 methods agree | Not in label — unassessed | serious PRR 4.4 · 70% consumer | no trial data cached |
| Dry eye | 23 | 3.5 2.4–5.3ROR 3.6 · χ² 40 / p 2e-10 | 3.3 EB05 2.4 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | serious PRR 5.7 | no trial data cached |
| Balance disorder | 41 | 3.5 2.6–4.8ROR 3.6 · χ² 72 / p 8e-18 | 3.4 EB05 2.6 · IC025 +1.3 3/3 methods agree | Not in label — unassessed | serious PRR 3.2 | no trial data cached |
| Dysphonia | 27 | 3.5 2.4–5.0ROR 3.5 · χ² 45 / p 1e-11 | 3.3 EB05 2.4 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | serious PRR 2.7 | no trial data cached |
| Eye swelling | 17 | 3.4 2.1–5.5ROR 3.5 · χ² 27 / p 1e-7 | 3.2 EB05 2.1 · IC025 +0.9 3/3 methods agree | Not in label — unassessed | serious PRR 3.1 | no trial data cached |
| Musculoskeletal pain | 24 | 3.4 2.3–5.1ROR 3.4 · χ² 38 / p 3e-10 | 3.2 EB05 2.3 · IC025 +1.0 3/3 methods agree | Not in label — unassessed | serious PRR 3.9 | no trial data cached |
| Anger | 15 | 3.3 2.0–5.5ROR 3.3 · χ² 22 / p 1e-6 | 3.1 EB05 2.0 · IC025 +0.7 | Not in label — unassessed | serious PRR 5.3 | no trial data cached |
| Abasia | 11 | 3.3 1.8–5.9ROR 3.3 · χ² 15 / p 5e-5 | 3.0 EB05 1.8 · IC025 +0.6 | Not in label — unassessed | serious PRR 3.5 | no trial data cached |
| Panic attack | 16 | 3.3 2.0–5.3ROR 3.3 · χ² 23 / p 8e-7 | 3.0 EB05 2.0 · IC025 +0.8 3/3 methods agree | Not in label — unassessed | serious PRR 4.0 | no trial data cached |
| Feeling cold | 12 | 3.2 1.8–5.7ROR 3.2 · χ² 16 / p 3e-5 | 2.9 EB05 1.8 · IC025 +0.6 | Not in label — unassessed | serious PRR 2.8 | no trial data cached |
Trial evidence (ClinicalTrials.gov)
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 |
|---|---|---|---|---|---|---|
| Feeling abnormal | 98 | 3.0 2.5–3.7ROR 3.1 · χ² 134 / p 3e-31 | 3.0 EB05 2.5 · IC025 +1.3 3/3 methods agree | Not in label — unassessed | serious PRR 4.0 · 78% consumer | no trial data cached |
| Gait disturbance | 93 | 3.6 3.0–4.4ROR 3.7 · χ² 175 / p 2e-40 | 3.6 EB05 3.0 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 3.8 · 77% consumer | no trial data cached |
| Myalgia (muscle pain) | 67 | 2.9 2.3–3.7ROR 3.0 · χ² 85 / p 2e-20 | 2.9 EB05 2.4 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | serious PRR 2.8 · 71% consumer | no trial data cached |
| Injection site pain (pain where injected) | 48 | 1.2 0.9–1.6ROR 1.2 · χ² 1 / p 0.138 | 1.2 EB05 0.9 · IC025 -0.2 PRR-only: not supported by EBGM or IC | Not in label — unassessed | serious PRR 2.7 | no trial data cached |
| Influenza | 47 | 3.1 2.4–4.2ROR 3.2 · χ² 67 / p 1e-16 | 3.1 EB05 2.4 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | serious PRR 4.8 | no trial data cached |
| Balance disorder | 41 | 3.5 2.6–4.8ROR 3.6 · χ² 72 / p 8e-18 | 3.4 EB05 2.6 · IC025 +1.3 3/3 methods agree | Not in label — unassessed | serious PRR 3.2 | no trial data cached |
| Bone pain | 41 | 5.2 3.9–7.1ROR 5.3 · χ² 136 / p 9e-32 | 4.9 EB05 3.8 · IC025 +1.8 3/3 methods agree | Not in label — unassessed | serious PRR 8.3 · ♀ 62% (drug 85%) | no trial data cached |
| Rheumatoid arthritis | 37 | 2.4 1.8–3.4ROR 2.5 · χ² 30 / p 2e-8 | 2.4 EB05 1.8 · IC025 +0.7 | Not in label — unassessed | serious PRR 3.1 · ♀ 61% (drug 85%) | no trial data cached |
| Flushing | 36 | 2.6 1.9–3.6ROR 2.7 · χ² 35 / p 2e-9 | 2.6 EB05 1.9 · IC025 +0.8 | Not in label — unassessed | serious PRR 4.5 | no trial data cached |
| Drug dose omission | 30 | 1.3 0.9–1.9ROR 1.3 · χ² 2 / p 0.067 | 1.3 EB05 1.0 · IC025 -0.2 PRR-only: not supported by EBGM or IC | Reporting / coding artifact | serious PRR 2.3 · 76% consumer | no trial data cached |
| Hot flush (hot flashes) | 30 | 3.0 2.1–4.2ROR 3.0 · χ² 37 / p 5e-10 | 2.9 EB05 2.1 · IC025 +0.9 3/3 methods agree | Not in label — unassessed | serious PRR 4.3 | no trial data cached |
| Blood cholesterol increased | 30 | 4.8 3.4–6.9ROR 4.9 · χ² 87 / p 6e-21 | 4.5 EB05 3.3 · IC025 +1.6 3/3 methods agree | Lab value / disease marker | serious PRR 6.8 | no trial data cached |
| Product quality issue | 29 | 1.6 1.1–2.3ROR 1.6 · χ² 6 / p 0.007 | 1.6 EB05 1.2 · IC025 +0.1 | Reporting / coding artifact | serious PRR 2.0 | no trial data cached |
| Osteoarthritis | 29 | 5.1 3.6–7.3ROR 5.1 · χ² 92 / p 5e-22 | 4.7 EB05 3.5 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 6.5 · ♀ 56% (drug 85%) | no trial data cached |
| Dysphonia | 27 | 3.5 2.4–5.0ROR 3.5 · χ² 45 / p 1e-11 | 3.3 EB05 2.4 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | serious PRR 2.7 | no trial data cached |
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.
- Bone pain — n=41, PRR 5.2
- Osteoarthritis — n=29, PRR 5.1
- Gait disturbance — n=93, PRR 3.6
- Pollakiuria — n=20, PRR 3.6
- Dry eye — n=23, PRR 3.5
- Balance disorder — n=41, PRR 3.5
- Dysphonia — n=27, PRR 3.5
- Musculoskeletal pain — n=24, PRR 3.4
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 Thyroid?
In FDA FAERS, the most frequently co-reported reaction terms for Thyroid are feeling abnormal, gait disturbance, myalgia, injection site pain, influenza, balance disorder. 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 Thyroid have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: Drugs with thyroid hormone activity, alone or together with other therapeutic agents, have been used for the treatment of obesity. In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction.
Do FAERS signals prove that Thyroid 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 9b517204-3d73-410f-aa86-741f29e51906, effective 20250804; matched on
openfda.generic_name.exact:"THYROID") - 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, 188 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
Page generated 2026-10-08. 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.