Zaleplon side effects: what 1,588 FDA adverse event reports show
Drug class
gamma-Aminobutyric Acid A Receptor Agonist
Who reports
1,588 reports · 57% serious · 176 with death outcome · 68% female
Used for
Zaleplon capsules are indicated for the short-term treatment of insomnia. Zaleplon capsules have been shown to decrease the time to sleep onset for up to 30 days in controlled clinical studies (see Clinical Trials under CLINICAL PHARMACOLOGY ). It has not been shown to increase total sleep time or decrease the number of awakenings.
What it is
DESCRIPTION Zaleplon, USP is a nonbenzodiazepine hypnotic from the pyrazolopyrimidine class.
Boxed warning
COMPLEX SLEEP BEHAVIORS Complex sleep behaviors including sleep-walking, sleep-driving, and engaging in other activities while not fully awake may occur following use of zaleplon. Some of these events may result in serious injuries, including death.
Causality screen of the 15 strongest signals
What the badges mean
- 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.
- 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. 27 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 |
|---|---|---|---|---|---|---|
| Sleep apnoea syndrome | 26 | 18.0 12.3–26.3ROR 18.2 · χ² 399 / p 4e-89 | 17.6 EB05 12.5 · IC025 +3.1 3/3 methods agree | Labeled (related wording) related wording | serious PRR 20.7 | no trial data cached |
| Completed suicide (death by suicide) | 88 | 13.8 11.3–16.9ROR 14.6 · χ² 1,036 / p 1e-227 | 13.7 EB05 11.4 · IC025 +3.3 3/3 methods agree | Outcome field, not a reaction boxed warning mentions mortality | serious PRR 13.9 · 98% clinician | no trial data cached |
| Seasonal allergy | 12 | 11.2 6.4–19.7ROR 11.3 · χ² 102 / p 3e-24 | 9.5 EB05 5.3 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious n=7 | no trial data cached |
| Chronic kidney disease | 46 | 7.9 6.0–10.5ROR 8.1 · χ² 272 / p 2e-61 | 7.5 EB05 5.8 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 8.1 | no trial data cached |
| Middle insomnia | 10 | 7.1 3.8–13.2ROR 7.1 · χ² 46 / p 5e-12 | 5.6 EB05 3.2 · IC025 +1.4 3/3 methods agree | Labeled (related wording) related wording | serious PRR 1.6 | no trial data cached |
| Sedation | 14 | 7.1 4.2–11.9ROR 7.1 · χ² 67 / p 1e-16 | 5.9 EB05 3.7 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 5.6 | no trial data cached |
| Poor quality sleep | 11 | 6.8 3.8–12.2ROR 6.8 · χ² 49 / p 2e-12 | 5.5 EB05 3.2 · IC025 +1.4 3/3 methods agree | Reporting / coding artifact | serious PRR 3.4 | no trial data cached |
| Surgery | 26 | 5.9 4.0–8.7ROR 6.0 · χ² 102 / p 3e-24 | 5.4 EB05 3.9 · IC025 +1.8 3/3 methods agree | Reporting / coding artifact | serious PRR 6.6 | no trial data cached |
| Renal injury | 11 | 4.8 2.7–8.7ROR 4.9 · χ² 30 / p 2e-8 | 4.1 EB05 2.5 · IC025 +1.0 3/3 methods agree | Not in label — unassessed | serious PRR 4.9 | no trial data cached |
| Suicidal ideation (thoughts of suicide) | 28 | 4.0 2.8–5.8ROR 4.1 · χ² 61 / p 3e-15 | 3.8 EB05 2.8 · IC025 +1.3 3/3 methods agree | Not in label — unassessed | serious PRR 3.8 | no trial data cached |
| Toxicity to various agents | 44 | 3.5 2.6–4.6ROR 3.5 · χ² 75 / p 2e-18 | 3.4 EB05 2.6 · IC025 +1.2 3/3 methods agree | Not in label — unassessed | serious PRR 3.6 · 98% clinician | no trial data cached |
| Product substitution issue | 14 | 3.2 1.9–5.4ROR 3.2 · χ² 19 / p 6e-6 | 3.0 EB05 1.9 · IC025 +0.7 | Reporting / coding artifact | serious PRR 3.9 | no trial data cached |
| Suicide attempt | 13 | 2.8 1.6–4.9ROR 2.8 · χ² 14 / p 1e-4 | 2.6 EB05 1.7 · IC025 +0.5 | Not in label — unassessed | serious PRR 2.6 | no trial data cached |
| Intentional overdose | 12 | 2.5 1.4–4.4ROR 2.5 · χ² 9 / p 0.001 | 2.3 EB05 1.5 · IC025 +0.3 | Reporting / coding artifact | serious PRR 2.6 | no trial data cached |
| Multiple sclerosis relapse | 12 | 2.3 1.3–4.0ROR 2.3 · χ² 8 / p 0.003 | 2.2 EB05 1.4 · IC025 +0.1 | Not in label — unassessed | serious PRR 2.7 | 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 |
|---|---|---|---|---|---|---|
| Completed suicide (death by suicide) | 88 | 13.8 11.3–16.9ROR 14.6 · χ² 1,036 / p 1e-227 | 13.7 EB05 11.4 · IC025 +3.3 3/3 methods agree | Outcome field, not a reaction boxed warning mentions mortality | serious PRR 13.9 · 98% clinician | no trial data cached |
| Chronic kidney disease | 46 | 7.9 6.0–10.5ROR 8.1 · χ² 272 / p 2e-61 | 7.5 EB05 5.8 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 8.1 | no trial data cached |
| Toxicity to various agents | 44 | 3.5 2.6–4.6ROR 3.5 · χ² 75 / p 2e-18 | 3.4 EB05 2.6 · IC025 +1.2 3/3 methods agree | Not in label — unassessed | serious PRR 3.6 · 98% clinician | no trial data cached |
| Suicidal ideation (thoughts of suicide) | 28 | 4.0 2.8–5.8ROR 4.1 · χ² 61 / p 3e-15 | 3.8 EB05 2.8 · IC025 +1.3 3/3 methods agree | Not in label — unassessed | serious PRR 3.8 | no trial data cached |
| Surgery | 26 | 5.9 4.0–8.7ROR 6.0 · χ² 102 / p 3e-24 | 5.4 EB05 3.9 · IC025 +1.8 3/3 methods agree | Reporting / coding artifact | serious PRR 6.6 | no trial data cached |
| Sleep apnoea syndrome | 26 | 18.0 12.3–26.3ROR 18.2 · χ² 399 / p 4e-89 | 17.6 EB05 12.5 · IC025 +3.1 3/3 methods agree | Labeled (related wording) related wording | serious PRR 20.7 | no trial data cached |
| Product substitution issue | 14 | 3.2 1.9–5.4ROR 3.2 · χ² 19 / p 6e-6 | 3.0 EB05 1.9 · IC025 +0.7 | Reporting / coding artifact | serious PRR 3.9 | no trial data cached |
| Sedation | 14 | 7.1 4.2–11.9ROR 7.1 · χ² 67 / p 1e-16 | 5.9 EB05 3.7 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 5.6 | no trial data cached |
| Suicide attempt | 13 | 2.8 1.6–4.9ROR 2.8 · χ² 14 / p 1e-4 | 2.6 EB05 1.7 · IC025 +0.5 | Not in label — unassessed | serious PRR 2.6 | no trial data cached |
| Multiple sclerosis relapse | 12 | 2.3 1.3–4.0ROR 2.3 · χ² 8 / p 0.003 | 2.2 EB05 1.4 · IC025 +0.1 | Not in label — unassessed | serious PRR 2.7 | no trial data cached |
| Intentional overdose | 12 | 2.5 1.4–4.4ROR 2.5 · χ² 9 / p 0.001 | 2.3 EB05 1.5 · IC025 +0.3 | Reporting / coding artifact | serious PRR 2.6 | no trial data cached |
| Seasonal allergy | 12 | 11.2 6.4–19.7ROR 11.3 · χ² 102 / p 3e-24 | 9.5 EB05 5.3 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious n=7 | no trial data cached |
| Renal injury | 11 | 4.8 2.7–8.7ROR 4.9 · χ² 30 / p 2e-8 | 4.1 EB05 2.5 · IC025 +1.0 3/3 methods agree | Not in label — unassessed | serious PRR 4.9 | no trial data cached |
| Poor quality sleep | 11 | 6.8 3.8–12.2ROR 6.8 · χ² 49 / p 2e-12 | 5.5 EB05 3.2 · IC025 +1.4 3/3 methods agree | Reporting / coding artifact | serious PRR 3.4 | no trial data cached |
| Drug withdrawal syndrome | 10 | 1.5 0.8–2.8ROR 1.5 · χ² 1 / p 0.141 | 1.5 EB05 0.9 · IC025 -0.5 PRR-only: not supported by EBGM or IC | Labeled (related wording) related wording | serious PRR 1.7 | 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.
- Chronic kidney disease — n=46, PRR 7.9
- Suicidal ideation — n=28, PRR 4.0
- Toxicity to various agents — n=44, PRR 3.5
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 Zaleplon?
In FDA FAERS, the most frequently co-reported reaction terms for Zaleplon are chronic kidney disease, toxicity to various agents, suicidal ideation, sleep apnoea syndrome, sedation, suicide attempt. 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 Zaleplon have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: COMPLEX SLEEP BEHAVIORS Complex sleep behaviors including sleep-walking, sleep-driving, and engaging in other activities while not fully awake may occur following use of zaleplon. Some of these events may result in serious injuries, including death.
Do FAERS signals prove that Zaleplon 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 517953c8-22ad-41af-a869-b7e4e5b291ae, effective 20240816; matched on
openfda.generic_name.exact:"ZALEPLON") - 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, 42 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.