Selegiline Hydrochloride side effects: what 571 FDA adverse event reports show

Selegiline Hydrochloride · Emsam · 17 reaction terms · 245 drug–reaction co-reports · data 2026-09-14

Drug class

Monoamine Oxidase Inhibitor, Monoamine Oxidase Type B Inhibitor

FDA label (Established Pharmacologic Class)

Brand names

Emsam

openFDA label

Who reports

571 reports · 80% serious · 64 with death outcome · 47% female

openFDA FAERS counts, all years, deduplication not applied

Used for

EMSAM (selegiline transdermal system) is a monoamine oxidase inhibitor (MAOI) indicated for the treatment of adults with major depressive disorder (MDD) . EMSAM ® (selegiline transdermal system) is a monoamine oxidase inhibitor (MAOI) indicated for the treatment of major depressive disorder (MDD) ( 1 ).

FDA label, Indications and Usage

What it is

EMSAM ® contains selegiline, a MAOI antidepressant. When applied to intact skin, EMSAM is designed to transdermally deliver selegiline over a 24-hour period. Selegiline base is a colorless to yellow liquid, chemically described as (-)-( N )-Methyl- N -[(1 R )-1-methyl-2-phenylethyl]prop-2-yn-1-amine.

FDA label, Description section

Boxed warning

SUICIDAL THOUGHTS AND BEHAVIORS Antidepressants increased the risk of suicidal thoughts and behaviors in pediatric and young adult patients in short-term studies. Closely monitor all antidepressant-treated patients for clinical worsening, and for emergence of suicidal thoughts and behaviors [see Warnings and Precautions (5.1) ] .

FDA label

How to read this page. FAERS is a spontaneous-reporting system: counts are not incidence rates and a signal is not proof of causation. Each reaction below is run through an automated screen — is the term in the FDA label (known), in the indications (the disease being treated), an administrative/coding term, or none of these (unlabeled)? That screen is mechanical text matching, not a causality assessment. The 30 hand-written Bradford Hill assessments are on the causality assessment page. Not medical advice.

Causality screen of the 15 strongest signals

Labeled adverse reaction 2Labeled (related wording) 1Reporting / coding artifact 2Not in label — unassessed 10

What the badges mean

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.
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.
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. 2 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.

Show: hide coding/lab/outcome terms hide indication terms unlabeled only hide PRR-only

Reaction	Reports	PRR 95% CI · ROR · χ²/p	EBGM EB05 · IC025	Label screen	Serious-only & strata	Trial cross-check
Delusion	22	52.2 34.7–78.7ROR 54.3 · χ² 1,054 / p 1e-231	50.0 EB05 34.8 · IC025 +3.9 3/3 methods agree	Not in label — unassessed	serious PRR 39.3	no trial data cached
Hallucination, visual	28	49.1 34.2–70.4ROR 51.5 · χ² 1,270 / p 2e-278	47.5 EB05 34.5 · IC025 +4.1 3/3 methods agree	Labeled (related wording) related wording	serious PRR 36.2	no trial data cached
Dyskinesia (involuntary movements)	42	38.1 28.4–50.9ROR 41.0 · χ² 1,480 / p <1e-300	37.4 EB05 28.9 · IC025 +4.2 3/3 methods agree	Not in label — unassessed	serious PRR 35.7	no trial data cached
Muscle rigidity	11	33.8 18.8–60.8ROR 34.5 · χ² 318 / p 2e-71	32.1 EB05 19.1 · IC025 +2.8 3/3 methods agree	Not in label — unassessed	serious PRR 27.5	no trial data cached
Hallucination (hallucinations)	62	30.4 24.0–38.5ROR 34.0 · χ² 1,738 / p <1e-300	30.1 EB05 24.3 · IC025 +4.2 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 23.3	no trial data cached
Paranoia	11	23.3 13.0–41.9ROR 23.8 · χ² 213 / p 1e-48	22.3 EB05 12.9 · IC025 +2.5 3/3 methods agree	Not in label — unassessed	serious PRR 15.4	no trial data cached
Orthostatic hypotension (dizziness on standing)	9	18.9 9.9–36.2ROR 19.2 · χ² 136 / p 1e-31	17.4 EB05 8.5 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 15.6	no trial data cached
Neuroleptic malignant syndrome	6	18.5 8.4–41.1ROR 18.7 · χ² 83 / p 5e-20	15.3 EB05 5.6 · IC025 +1.6 3/3 methods agree	Not in label — unassessed	serious PRR 13.5	no trial data cached
Hallucination, auditory	8	18.5 9.3–36.8ROR 18.7 · χ² 115 / p 3e-27	16.5 EB05 7.4 · IC025 +2.0 3/3 methods agree	Not in label — unassessed	serious PRR 15.4	no trial data cached
Serotonin syndrome	9	17.3 9.0–33.1ROR 17.5 · χ² 122 / p 1e-28	15.6 EB05 7.4 · IC025 +2.1 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 12.6	no trial data cached
Sopor	6	16.5 7.4–36.6ROR 16.7 · χ² 73 / p 8e-18	13.0 EB05 4.8 · IC025 +1.5 3/3 methods agree	Not in label — unassessed	serious PRR 11.9	no trial data cached
Psychomotor hyperactivity	7	15.4 7.4–32.2ROR 15.6 · χ² 81 / p 1e-19	12.6 EB05 5.2 · IC025 +1.7 3/3 methods agree	Not in label — unassessed	serious PRR 18.5	no trial data cached
Dystonia	6	11.3 5.1–25.1ROR 11.4 · χ² 47 / p 4e-12	7.9 EB05 3.4 · IC025 +1.2 3/3 methods agree	Not in label — unassessed	serious PRR 9.1	no trial data cached
Product complaint	6	8.8 4.0–19.6ROR 8.9 · χ² 34 / p 2e-9	6.0 EB05 2.8 · IC025 +1.0 3/3 methods agree	Reporting / coding artifact	serious n=6	no trial data cached
Therapeutic response shortened	5	5.8 2.4–13.8ROR 5.8 · χ² 15 / p 5e-5	4.0 EB05 1.9 · IC025 +0.4	Reporting / coding artifact	serious PRR 12.3	no trial data cached

Trial evidence (ClinicalTrials.gov)

Trial cross-check not yet run for this drug (ClinicalTrials.gov pull covers the 800 most-reported drugs first).

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
Hallucination (hallucinations)	62	30.4 24.0–38.5ROR 34.0 · χ² 1,738 / p <1e-300	30.1 EB05 24.3 · IC025 +4.2 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 23.3	no trial data cached
Dyskinesia (involuntary movements)	42	38.1 28.4–50.9ROR 41.0 · χ² 1,480 / p <1e-300	37.4 EB05 28.9 · IC025 +4.2 3/3 methods agree	Not in label — unassessed	serious PRR 35.7	no trial data cached
Hallucination, visual	28	49.1 34.2–70.4ROR 51.5 · χ² 1,270 / p 2e-278	47.5 EB05 34.5 · IC025 +4.1 3/3 methods agree	Labeled (related wording) related wording	serious PRR 36.2	no trial data cached
Delusion	22	52.2 34.7–78.7ROR 54.3 · χ² 1,054 / p 1e-231	50.0 EB05 34.8 · IC025 +3.9 3/3 methods agree	Not in label — unassessed	serious PRR 39.3	no trial data cached
Paranoia	11	23.3 13.0–41.9ROR 23.8 · χ² 213 / p 1e-48	22.3 EB05 12.9 · IC025 +2.5 3/3 methods agree	Not in label — unassessed	serious PRR 15.4	no trial data cached
Muscle rigidity	11	33.8 18.8–60.8ROR 34.5 · χ² 318 / p 2e-71	32.1 EB05 19.1 · IC025 +2.8 3/3 methods agree	Not in label — unassessed	serious PRR 27.5	no trial data cached
Serotonin syndrome	9	17.3 9.0–33.1ROR 17.5 · χ² 122 / p 1e-28	15.6 EB05 7.4 · IC025 +2.1 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 12.6	no trial data cached
Orthostatic hypotension (dizziness on standing)	9	18.9 9.9–36.2ROR 19.2 · χ² 136 / p 1e-31	17.4 EB05 8.5 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 15.6	no trial data cached
Hallucination, auditory	8	18.5 9.3–36.8ROR 18.7 · χ² 115 / p 3e-27	16.5 EB05 7.4 · IC025 +2.0 3/3 methods agree	Not in label — unassessed	serious PRR 15.4	no trial data cached
Psychomotor hyperactivity	7	15.4 7.4–32.2ROR 15.6 · χ² 81 / p 1e-19	12.6 EB05 5.2 · IC025 +1.7 3/3 methods agree	Not in label — unassessed	serious PRR 18.5	no trial data cached
Product complaint	6	8.8 4.0–19.6ROR 8.9 · χ² 34 / p 2e-9	6.0 EB05 2.8 · IC025 +1.0 3/3 methods agree	Reporting / coding artifact	serious n=6	no trial data cached
Dystonia	6	11.3 5.1–25.1ROR 11.4 · χ² 47 / p 4e-12	7.9 EB05 3.4 · IC025 +1.2 3/3 methods agree	Not in label — unassessed	serious PRR 9.1	no trial data cached
Sopor	6	16.5 7.4–36.6ROR 16.7 · χ² 73 / p 8e-18	13.0 EB05 4.8 · IC025 +1.5 3/3 methods agree	Not in label — unassessed	serious PRR 11.9	no trial data cached
Neuroleptic malignant syndrome	6	18.5 8.4–41.1ROR 18.7 · χ² 83 / p 5e-20	15.3 EB05 5.6 · IC025 +1.6 3/3 methods agree	Not in label — unassessed	serious PRR 13.5	no trial data cached
Therapeutic response shortened	5	5.8 2.4–13.8ROR 5.8 · χ² 15 / p 5e-5	4.0 EB05 1.9 · IC025 +0.4	Reporting / coding artifact	serious PRR 12.3	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.

Delusion — n=22, PRR 52.2
Dyskinesia — n=42, PRR 38.1

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 Selegiline?

In FDA FAERS, the most frequently co-reported reaction terms for Selegiline are hallucination, dyskinesia, hallucination, visual, delusion, paranoia, muscle rigidity. 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 Selegiline have an FDA boxed warning?

Yes. The current FDA label carries a boxed warning: SUICIDAL THOUGHTS AND BEHAVIORS Antidepressants increased the risk of suicidal thoughts and behaviors in pediatric and young adult patients in short-term studies. Closely monitor all antidepressant-treated patients for clinical worsening, and for emergence of suicidal thoughts and behaviors [see Warnings and Precautions (5.1) ] .

Do FAERS signals prove that Selegiline 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 b891bd9f-fdb8-4862-89c5-ecdd700398a3, effective 20200515; matched on openfda.generic_name.exact:"SELEGILINE")
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, field patient.drug.openfda.generic_name.exact, 17 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.