Methylphenidate HCL side effects: what 1,270 FDA adverse event reports show
Drug class
Central Nervous System Stimulant
Who reports
1,270 reports · 84% serious · 130 with death outcome · 38% female
Used for
Methylphenidate transdermal system is indicated for the treatment of Attention Deficit Hyperactivity Disorder (ADHD) in pediatric patients 6 to 17 years of age. Limitations of Us e The use of methylphenidate transdermal system is not recommended in ped.
What it is
Methylphenidate transdermal system is an adhesive-based matrix transdermal system containing methylphenidate that is applied to intact skin.
Boxed warning
ABUSE, MISUSE, AND ADDICTION Methylphenidate transdermal system has a high potential for abuse and misuse, which can lead to the development of substance use disorder, including addiction. Misuse and abuse of CNS sti.
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.
- Labeled adverse reaction The exact term appears in the label's warnings or adverse-reactions sections: a known, expected effect. The FAERS signal confirms the label rather than discovering anything.
- Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
- 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.
- Outcome field, not a reaction Death is a report outcome, not a reaction term. It is dominated by the underlying illness; see the seriousness profile and the boxed warning instead.
- 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. 32 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 |
|---|---|---|---|---|---|---|
| Mania | 22 | 22.1 14.6–33.5ROR 22.5 · χ² 423 / p 3e-94 | 21.7 EB05 15.0 · IC025 +3.2 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 18.6 · ♀ 14% (drug 38%) | no trial data cached |
| Apathy | 19 | 21.6 13.8–33.8ROR 21.9 · χ² 353 / p 5e-79 | 21.1 EB05 14.2 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 11.2 | no trial data cached |
| Affect lability | 12 | 20.5 11.7–36.0ROR 20.7 · χ² 203 / p 2e-46 | 19.6 EB05 11.4 · IC025 +2.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 17.9 | no trial data cached |
| Aggression | 62 | 20.4 16.0–26.1ROR 21.4 · χ² 1,128 / p 1e-247 | 20.3 EB05 16.4 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious PRR 16.0 · ♀ 15% (drug 38%) | no trial data cached |
| Sudden death | 13 | 20.1 11.7–34.5ROR 20.3 · χ² 217 / p 2e-49 | 19.3 EB05 11.5 · IC025 +2.6 3/3 methods agree | Outcome field, not a reaction boxed warning mentions mortality | serious PRR 13.7 | no trial data cached |
| Gastrointestinal pain | 13 | 19.6 11.4–33.7ROR 19.8 · χ² 211 / p 4e-48 | 18.8 EB05 11.2 · IC025 +2.6 3/3 methods agree | Labeled (related wording) related wording | serious PRR 4.7 | no trial data cached |
| Abnormal behaviour | 44 | 18.2 13.6–24.4ROR 18.9 · χ² 700 / p 1e-154 | 18.1 EB05 14.0 · IC025 +3.4 3/3 methods agree | Not in label — unassessed | serious PRR 15.6 | no trial data cached |
| Hypotonia | 11 | 18.1 10.1–32.7ROR 18.3 · χ² 161 / p 3e-37 | 17.0 EB05 9.2 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 5.1 | no trial data cached |
| Grand mal convulsion | 10 | 17.6 9.5–32.7ROR 17.8 · χ² 141 / p 9e-33 | 16.2 EB05 8.3 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 12.2 | no trial data cached |
| Pharmaceutical product complaint | 27 | 16.9 11.7–24.6ROR 17.3 · χ² 389 / p 6e-87 | 16.6 EB05 11.8 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 11.1 | no trial data cached |
| Intentional drug misuse | 21 | 16.4 10.7–25.0ROR 16.6 · χ² 288 / p 8e-65 | 15.9 EB05 10.7 · IC025 +2.9 3/3 methods agree | Reporting / coding artifact | serious PRR 17.1 | no trial data cached |
| Dystonia | 19 | 16.1 10.3–25.2ROR 16.4 · χ² 255 / p 1e-57 | 15.6 EB05 10.1 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 12.1 | no trial data cached |
| Peripheral coldness | 13 | 15.6 9.1–26.8ROR 15.7 · χ² 163 / p 1e-37 | 14.5 EB05 8.2 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 14.9 | no trial data cached |
| Drug toxicity | 13 | 15.6 9.1–26.7ROR 15.7 · χ² 163 / p 1e-37 | 14.5 EB05 8.2 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 10.2 | no trial data cached |
| Serotonin syndrome | 18 | 15.5 9.8–24.6ROR 15.8 · χ² 231 / p 2e-52 | 14.9 EB05 9.5 · IC025 +2.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 10.7 | no trial data cached |
| Psychomotor hyperactivity | 14 | 13.9 8.2–23.4ROR 14.0 · χ² 155 / p 8e-36 | 12.7 EB05 7.3 · IC025 +2.4 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious PRR 9.0 | no trial data cached |
| Coordination abnormal | 11 | 12.9 7.2–23.3ROR 13.0 · χ² 110 / p 6e-26 | 11.2 EB05 5.8 · IC025 +2.1 3/3 methods agree | Not in label — unassessed | serious PRR 11.1 | no trial data cached |
| Mydriasis | 10 | 12.9 6.9–23.9ROR 13.0 · χ² 98 / p 2e-23 | 10.9 EB05 5.5 · IC025 +2.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 11.4 | no trial data cached |
| Anorexia | 10 | 12.6 6.8–23.4ROR 12.7 · χ² 96 / p 6e-23 | 10.6 EB05 5.4 · IC025 +1.9 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 9.1 | no trial data cached |
| Delusion | 11 | 11.7 6.5–21.1ROR 11.8 · χ² 98 / p 3e-23 | 9.9 EB05 5.2 · IC025 +2.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 9.7 | no trial data cached |
| Sinus tachycardia | 10 | 11.7 6.3–21.6ROR 11.7 · χ² 87 / p 5e-21 | 9.6 EB05 4.9 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 8.1 | no trial data cached |
| Hallucination, auditory | 10 | 10.4 5.6–19.2ROR 10.5 · χ² 76 / p 2e-18 | 8.3 EB05 4.4 · IC025 +1.8 3/3 methods agree | Not in label — unassessed | serious PRR 6.5 | no trial data cached |
| Convulsion (seizure) | 36 | 10.3 7.4–14.2ROR 10.5 · χ² 292 / p 9e-66 | 9.7 EB05 7.2 · IC025 +2.6 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 7.2 | no trial data cached |
| Respiratory arrest | 17 | 10.1 6.3–16.2ROR 10.2 · χ² 130 / p 2e-30 | 8.9 EB05 5.5 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 6.9 | no trial data cached |
| Agitation | 45 | 10.1 7.6–13.4ROR 10.4 · χ² 361 / p 1e-80 | 9.7 EB05 7.4 · IC025 +2.7 3/3 methods agree | Not in label — unassessed | serious PRR 7.7 | no trial data cached |
| Psychotic disorder | 18 | 10.1 6.4–15.9ROR 10.2 · χ² 138 / p 3e-32 | 8.9 EB05 5.7 · IC025 +2.2 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.1 | no trial data cached |
| Crying | 21 | 9.5 6.2–14.5ROR 9.7 · χ² 152 / p 4e-35 | 8.5 EB05 5.6 · IC025 +2.3 3/3 methods agree | Not in label — unassessed | serious PRR 6.3 | no trial data cached |
| Hallucination, visual | 12 | 9.4 5.4–16.6ROR 9.5 · χ² 82 / p 6e-20 | 7.7 EB05 4.4 · IC025 +1.8 3/3 methods agree | Labeled (related wording) related wording | serious PRR 7.4 | no trial data cached |
| Irritability | 34 | 9.3 6.7–13.0ROR 9.6 · χ² 245 / p 2e-55 | 8.7 EB05 6.4 · IC025 +2.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.9 | no trial data cached |
| Suicide attempt | 33 | 9.0 6.4–12.6ROR 9.2 · χ² 226 / p 2e-51 | 8.3 EB05 6.1 · IC025 +2.4 3/3 methods agree | Labeled (related wording) related wording | serious PRR 5.9 | no trial data cached |
| Completed suicide (death by suicide) | 45 | 8.8 6.6–11.8ROR 9.1 · χ² 306 / p 8e-69 | 8.4 EB05 6.4 · IC025 +2.5 3/3 methods agree | Outcome field, not a reaction boxed warning mentions mortality | serious PRR 6.0 · 91% clinician | no trial data cached |
| Intentional overdose | 34 | 8.8 6.3–12.3ROR 9.0 · χ² 228 / p 7e-52 | 8.2 EB05 6.0 · IC025 +2.4 3/3 methods agree | Reporting / coding artifact | serious PRR 6.1 | no trial data cached |
| Dysarthria (slurred speech) | 20 | 8.8 5.7–13.6ROR 8.9 · χ² 130 / p 2e-30 | 7.7 EB05 5.1 · IC025 +2.1 3/3 methods agree | Not in label — unassessed | serious PRR 7.1 | no trial data cached |
| Pallor | 14 | 8.5 5.0–14.3ROR 8.6 · χ² 85 / p 1e-20 | 7.1 EB05 4.3 · IC025 +1.8 3/3 methods agree | Not in label — unassessed | serious PRR 7.6 | no trial data cached |
| Drug effect decreased | 28 | 8.5 5.9–12.2ROR 8.6 · χ² 177 / p 1e-40 | 7.7 EB05 5.5 · IC025 +2.3 3/3 methods agree | Reporting / coding artifact | serious PRR 10.6 | no trial data cached |
| Disorientation | 19 | 7.9 5.1–12.3ROR 8.0 · χ² 108 / p 1e-25 | 6.9 EB05 4.6 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 6.6 | no trial data cached |
| Disturbance in attention | 25 | 7.6 5.2–11.3ROR 7.8 · χ² 138 / p 4e-32 | 6.9 EB05 4.8 · IC025 +2.1 3/3 methods agree | Labeled (related wording) related wording | serious PRR 5.6 | no trial data cached |
| Cardiac arrest (heart stopping) | 36 | 7.2 5.2–9.9ROR 7.4 · χ² 186 / p 1e-42 | 6.7 EB05 5.0 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 4.9 · 93% clinician | no trial data cached |
| Emotional disorder | 13 | 6.9 4.0–11.9ROR 7.0 · χ² 60 / p 4e-15 | 5.7 EB05 3.5 · IC025 +1.6 3/3 methods agree | Labeled (related wording) related wording | serious PRR 7.3 | no trial data cached |
| Restlessness | 15 | 6.8 4.1–11.2ROR 6.8 · χ² 68 / p 8e-17 | 5.7 EB05 3.7 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 6.2 | 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 |
|---|---|---|---|---|---|---|
| Aggression | 62 | 20.4 16.0–26.1ROR 21.4 · χ² 1,128 / p 1e-247 | 20.3 EB05 16.4 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious PRR 16.0 · ♀ 15% (drug 38%) | no trial data cached |
| Completed suicide (death by suicide) | 45 | 8.8 6.6–11.8ROR 9.1 · χ² 306 / p 8e-69 | 8.4 EB05 6.4 · IC025 +2.5 3/3 methods agree | Outcome field, not a reaction boxed warning mentions mortality | serious PRR 6.0 · 91% clinician | no trial data cached |
| Agitation | 45 | 10.1 7.6–13.4ROR 10.4 · χ² 361 / p 1e-80 | 9.7 EB05 7.4 · IC025 +2.7 3/3 methods agree | Not in label — unassessed | serious PRR 7.7 | no trial data cached |
| Abnormal behaviour | 44 | 18.2 13.6–24.4ROR 18.9 · χ² 700 / p 1e-154 | 18.1 EB05 14.0 · IC025 +3.4 3/3 methods agree | Not in label — unassessed | serious PRR 15.6 | no trial data cached |
| Cardiac arrest (heart stopping) | 36 | 7.2 5.2–9.9ROR 7.4 · χ² 186 / p 1e-42 | 6.7 EB05 5.0 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 4.9 · 93% clinician | no trial data cached |
| Convulsion (seizure) | 36 | 10.3 7.4–14.2ROR 10.5 · χ² 292 / p 9e-66 | 9.7 EB05 7.2 · IC025 +2.6 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 7.2 | no trial data cached |
| Intentional overdose | 34 | 8.8 6.3–12.3ROR 9.0 · χ² 228 / p 7e-52 | 8.2 EB05 6.0 · IC025 +2.4 3/3 methods agree | Reporting / coding artifact | serious PRR 6.1 | no trial data cached |
| Irritability | 34 | 9.3 6.7–13.0ROR 9.6 · χ² 245 / p 2e-55 | 8.7 EB05 6.4 · IC025 +2.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.9 | no trial data cached |
| Suicidal ideation (thoughts of suicide) | 33 | 5.9 4.2–8.3ROR 6.1 · χ² 131 / p 1e-30 | 5.5 EB05 4.1 · IC025 +1.9 3/3 methods agree | Labeled (related wording) related wording | serious PRR 4.1 | no trial data cached |
| Suicide attempt | 33 | 9.0 6.4–12.6ROR 9.2 · χ² 226 / p 2e-51 | 8.3 EB05 6.1 · IC025 +2.4 3/3 methods agree | Labeled (related wording) related wording | serious PRR 5.9 | no trial data cached |
| Drug effect decreased | 28 | 8.5 5.9–12.2ROR 8.6 · χ² 177 / p 1e-40 | 7.7 EB05 5.5 · IC025 +2.3 3/3 methods agree | Reporting / coding artifact | serious PRR 10.6 | no trial data cached |
| Pharmaceutical product complaint | 27 | 16.9 11.7–24.6ROR 17.3 · χ² 389 / p 6e-87 | 16.6 EB05 11.8 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 11.1 | no trial data cached |
| Disturbance in attention | 25 | 7.6 5.2–11.3ROR 7.8 · χ² 138 / p 4e-32 | 6.9 EB05 4.8 · IC025 +2.1 3/3 methods agree | Labeled (related wording) related wording | serious PRR 5.6 | no trial data cached |
| Mania | 22 | 22.1 14.6–33.5ROR 22.5 · χ² 423 / p 3e-94 | 21.7 EB05 15.0 · IC025 +3.2 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 18.6 · ♀ 14% (drug 38%) | no trial data cached |
| Product substitution issue | 21 | 6.0 3.9–9.2ROR 6.1 · χ² 83 / p 4e-20 | 5.4 EB05 3.7 · IC025 +1.7 3/3 methods agree | Reporting / coding artifact | serious PRR 5.4 | 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.
- Aggression — n=62, PRR 20.4
- Abnormal behaviour — n=44, PRR 18.2
- Pharmaceutical product complaint — n=27, PRR 16.9
- Agitation — n=45, PRR 10.1
- Crying — n=21, PRR 9.5
- Dysarthria — n=20, PRR 8.8
- Cardiac arrest — n=36, PRR 7.2
✓ A hand-written Bradford Hill causality assessment exists for this drug: Methylphenidate ↔ Hallucination, visual.
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 Methylphenidate?
In FDA FAERS, the most frequently co-reported reaction terms for Methylphenidate are aggression, agitation, abnormal behaviour, cardiac arrest, convulsion, irritability. 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 Methylphenidate have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: ABUSE, MISUSE, AND ADDICTION Methylphenidate transdermal system has a high potential for abuse and misuse, which can lead to the development of substance use disorder, including addiction. Misuse and abuse of CNS sti.
Do FAERS signals prove that Methylphenidate 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 1643b6a5-80da-4d4f-8c5f-feb907875702, effective 20251007; matched on
openfda.generic_name.exact:"METHYLPHENIDATE") - 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, 72 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.