Public record

Naltrexone: the public record

5 tables from US federal sources. Latest data date: Nov 11, 2026.

Each table is computed from the named federal dataset as of its data date; the method is under each one.

Approvals

FDA approval history for naltrexone

The earliest FDA approval on file for a naltrexone product is 1984-11-20. Drugs@FDA lists 10 applications for it and 56 approved supplements, the most recent on 2025-12-22.

FDA approval history for naltrexone: the figures
MeasureValueNote
Earliest FDA approval on file1984-11-20
Applications with an approval on file10
New drug applications (NDA)2
Generic applications (ANDA)8
Approved supplements56label, manufacturing and efficacy changes
Most recent supplement approval2025-12-22
Sponsoring companies10

Source: FDA, Drugs@FDA, data as of Nov 11, 2026

How this was calculated

Selected applications with a product whose only active ingredient is this substance, then counted approved original and supplemental submissions. The earliest approved original submission is the first approval.

Scope: Applications with a single-ingredient naltrexone product in Drugs@FDA, all sponsors and strengths

Older approvals can be missing dates, and tentative approvals are not counted. An approved application does not mean the product is currently marketed.

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Patents and generics

Patents and generic approvals for naltrexone

The FDA Orange Book lists 8 approved generic applications for naltrexone, the first approved on 1998-05-08. 1 listed patent on specific brand products has not yet expired, the last on 2029-10-15; generics of other versions are already approved.

Patents and generic approvals for naltrexone: the figures
MeasureValueNote
Brand-name applications (NDA)2
Approved generic applications (ANDA)8first approved 1998-05-08
Companies with a generic not marked discontinued7
Listed patents not yet expired1
Latest listed patent expiry2029-10-15on any product; may cover only one brand formulation
Earliest approval date on file1984-11-20
Products not marked discontinued10 of 12

Source: FDA, Orange Book (Approved Drug Products with Therapeutic Equivalence Evaluations), data as of Oct 9, 2026

How this was calculated

Selected Orange Book products whose only active ingredient is this substance, then counted applications by type and the distinct patents and exclusivities listed against them. Expired patents are left out.

Scope: All single-ingredient naltrexone products in the Orange Book, every brand and strength, files dated 2026-10-09

An approved generic or an expired patent does not show that a generic is on sale. Launch timing also depends on litigation, settlements and supply. Biologics and compounded products are not in the Orange Book.

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Adverse event reports

Most reported events in FDA adverse event reports for naltrexone

Through 2026-10-28, FDA had received 32,182 adverse event reports for naltrexone, 9,422 of them marked serious by the reporter. The symptom terms named most often were injection site reaction (4,389), injection site pain (3,172) and nausea (2,244).

Most reported events in FDA adverse event reports for naltrexone: the figures
MeasureValueNote
All reports received32,182
Reports the reporter marked serious9,422death, hospitalisation, disability or similar outcome
Injection site reaction4,389 reports
Injection site pain3,172 reports
Nausea2,244 reports
Fatigue2,012 reports
Alcoholism1,956 reports

Source: FDA Adverse Event Reporting System (FAERS) via openFDA, data as of Oct 28, 2026

How this was calculated

Counted FAERS reports listing this active substance, then the reaction terms named most often. A report can name several reactions, and a term can describe the illness being treated and not an effect of the drug.

Scope: Reports where FDA recorded naltrexone as a single-ingredient active substance (any brand), all years to 2026-10-28

FAERS reports are unverified and do not prove the drug caused the event. Reporting rises with use, publicity and lawsuits, so these counts cannot give rates or risks and cannot be compared between drugs.

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Recalls

FDA drug recalls naming naltrexone

FDA enforcement reports list 15 drug recall entries naming naltrexone from 2013 to 2022-06-15. 14 of them are for compounded or other unlisted products and 1 for products FDA lists under a label. The most common stated reason was lack of sterility assurance (5 of 15).

FDA drug recalls naming naltrexone: the figures
MeasureValueNote
Recall entries on record15
For products FDA lists under an approved or registered label1
For compounded or other unlisted products14matched by the name in the product description
Class I (most serious)0
Class II15
Class III0
Most recent recall reported2022-06-15
Most common stated reasonlack of sterility assurance5 of 15 entries

Source: FDA, Enforcement Reports (drug recalls) via openFDA, data as of Nov 10, 2026

How this was calculated

Counted enforcement report entries matched by FDA's listed active substance, or by the name in the product description where FDA lists none. Reasons were grouped by keywords in FDA's stated reason.

Scope: Recalls of single-ingredient naltrexone products, plus compounded or unlisted products whose description names it

Each recall covers specific lots from one firm and is not a statement about every product with this ingredient. One event can appear as several entries, one per product.

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Clinical studies

Registered clinical studies of naltrexone

ClinicalTrials.gov lists 538 registered studies that name naltrexone as an intervention as of 2026-11-11. Of these, 30 are recruiting, 383 are completed and 103 are phase 3 studies.

Registered clinical studies of naltrexone: the figures
MeasureValue
Registered studies538
Recruiting now30
Not yet recruiting16
Completed383
Terminated, withdrawn or suspended63
Phase 3 (including phase 2/3)103
Phase 2 (including phase 1/2)155
Phase 185

Source: NIH National Library of Medicine, ClinicalTrials.gov, data as of Nov 11, 2026

How this was calculated

Searched the ClinicalTrials.gov intervention field for the name, downloaded every matching record and counted by overall status and phase. Combined phases are counted under the higher phase. Phase not applicable covers observational, device and behavioural studies.

Scope: Studies whose intervention field matches naltrexone, any condition, any country, all statuses

A registered study is not a result. Counts include studies where the drug is a comparator or background treatment, and studies that never finished or reported.

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Articles on Naltrexone