FDA Study: 5.6% of Healthy Adults on CBD Developed Significant Liver Enzyme Elevations

In a rigorous FDA-conducted trial, 5.6% of healthy adults taking a consumer-relevant CBD dose for 28 days developed liver enzyme elevations more than 3 times the normal limit.

Florian, Jeffry et al.·JAMA internal medicine·2025·Strong EvidenceRandomized Controlled Trial
RTHC-06471Randomized Controlled TrialStrong Evidence2025RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Randomized Controlled Trial
Evidence
Strong Evidence
Sample
N=201

What This Study Found

8 of 143 participants (5.6%) taking CBD at 5 mg/kg/day developed ALT or AST elevations >3x ULN, vs 0 of 58 on placebo. Seven met withdrawal criteria for potential drug-induced liver injury, detected at days 21-28. No endocrine hormone changes observed.

Key Numbers

201 participants (median age 36, 44% female). CBD: 8/143 (5.6%, 95% CI 1.8-9.3%) with ALT/AST >3x ULN. Placebo: 0/58. 7 met DILI criteria. No endocrine changes.

How They Did This

Randomized double-blind placebo-controlled trial by FDA researchers. 201 healthy adults, CBD 5 mg/kg/day vs placebo for 28 days. Weekly liver enzyme monitoring.

Why This Research Matters

This is the first rigorous trial testing CBD liver safety at doses consumers actually use. The 5.6% incidence in healthy people over just 4 weeks is a notable safety signal.

The Bigger Picture

Millions of consumers use unregulated CBD products without liver monitoring. This trial suggests a small but meaningful percentage may develop liver injury at commonly used doses.

What This Study Doesn't Tell Us

Only 28 days. Pharmaceutical-grade CBD. Per protocol analysis. Healthy adults only. Relatively small sample.

Questions This Raises

  • ?What is the risk with longer use?
  • ?Are certain people genetically predisposed?
  • ?Should routine liver monitoring be recommended for CBD users?

Trust & Context

Key Stat:
5.6% developed liver enzyme elevations >3x normal in just 28 days
Evidence Grade:
Randomized, double-blind, placebo-controlled trial by FDA researchers with objective lab measurements.
Study Age:
2025 study
Original Title:
Cannabidiol and Liver Enzyme Level Elevations in Healthy Adults: A Randomized Clinical Trial.
Published In:
JAMA internal medicine, 185(9), 1070-1078 (2025)
Database ID:
RTHC-06471

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled TrialGold standard for testing treatments
This study
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal Study

Participants are randomly assigned to treatment or placebo groups to test cause and effect.

What do these levels mean? →

Frequently Asked Questions

What dose of CBD was used?

Participants took 5 mg/kg/day, within the range consumers commonly use. For a 150-pound person, that is about 340 mg/day.

Should I get my liver checked if I use CBD?

Liver enzyme elevations appeared at weeks 3-4. The study authors called for further investigation of long-term effects.

Read More on RethinkTHC

Cite This Study

RTHC-06471·https://rethinkthc.com/research/RTHC-06471

APA

Florian, Jeffry; Salcedo, Pablo; Burkhart, Keith; Shah, Aanchal; Chekka, Lakshmi Manasa S; Keshishi, Dro; Patel, Vikram; Yang, ShanChao; Fein, Melanie; DePalma, Ryan; Matta, Murali; Strauss, David G; Rouse, Rodney. (2025). Cannabidiol and Liver Enzyme Level Elevations in Healthy Adults: A Randomized Clinical Trial.. JAMA internal medicine, 185(9), 1070-1078. https://doi.org/10.1001/jamainternmed.2025.2366

MLA

Florian, Jeffry, et al. "Cannabidiol and Liver Enzyme Level Elevations in Healthy Adults: A Randomized Clinical Trial.." JAMA internal medicine, 2025. https://doi.org/10.1001/jamainternmed.2025.2366

RethinkTHC

RethinkTHC Research Database. "Cannabidiol and Liver Enzyme Level Elevations in Healthy Adu..." RTHC-06471. Retrieved from https://rethinkthc.com/research/florian-2025-cannabidiol-and-liver-enzyme

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.