Rhesus monkeys develop physical dependence on THC with daily use

Rhesus monkeys given THC twice daily developed clear physical dependence, showing a 20-fold increase in activity when withdrawal was triggered, while monkeys given THC only every 3 days did not.

Wilkerson, Jenny L et al.·PloS one·2019·Preliminary EvidenceAnimal StudyAnimal Study
RTHC-02349Animal StudyPreliminary Evidence2019RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Animal Study
Evidence
Preliminary Evidence
Sample
Not reported

What This Study Found

Chronic THC (1 mg/kg every 12 hours) produced dependence: rimonabant-precipitated withdrawal caused up to 20-fold increase in home-cage activity. Intermittent THC (0.1 mg/kg every 3 days) did not produce dependence signs. Abrupt discontinuation of chronic THC caused immediate (within 24 hours) and progressive increases in activity. THC was somewhat more potent in reducing activity in the intermittent group, consistent with tolerance development in the chronic group.

Key Numbers

Chronic: 1 mg/kg every 12 hours. Intermittent: 0.1 mg/kg every 3 days. Rimonabant doses: 0.1-3.2 mg/kg. Up to 20-fold activity increase during precipitated withdrawal. Spontaneous withdrawal began within 24 hours.

How They Did This

Two groups of rhesus monkeys: one receiving chronic THC (1 mg/kg every 12 hours) and one receiving intermittent THC (0.1 mg/kg every 3 days). Home-cage activity was measured continuously. Withdrawal was assessed via rimonabant challenge and abrupt discontinuation.

Why This Research Matters

Primate models are more translatable to humans than rodent models. This study establishes clear, measurable physical dependence in primates using a simple behavioral measure.

The Bigger Picture

The contrast between chronic and intermittent dosing directly parallels the human experience where daily heavy users report withdrawal but occasional users typically do not.

What This Study Doesn't Tell Us

Animal study (primates). Activity is only one measure of withdrawal. Dose and frequency may not directly correspond to human use patterns.

Questions This Raises

  • ?At what frequency of use does physical dependence begin to develop?
  • ?Would a gradual taper prevent the withdrawal activity increase?

Trust & Context

Key Stat:
20-fold activity increase during precipitated withdrawal
Evidence Grade:
Well-controlled primate study with objective behavioral measures, but animal model with limited sample size.
Study Age:
2019 preclinical study.
Original Title:
Tolerance and dependence to Δ9-tetrahydrocannabinol in rhesus monkeys: Activity assessments.
Published In:
PloS one, 14(3), e0209947 (2019)
Database ID:
RTHC-02349

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal StudyOne case or non-human subjects
This study

Tests effects in animals (usually mice or rats), not humans.

What do these levels mean? →

Frequently Asked Questions

Does daily cannabis use cause physical dependence?

In this primate study, monkeys receiving THC twice daily developed clear physical dependence with measurable withdrawal signs, while those receiving THC every 3 days did not.

What does THC withdrawal look like?

In these monkeys, withdrawal manifested as dramatic increases in home-cage activity (up to 20-fold), beginning within 24 hours of the last dose and increasing over time.

Read More on RethinkTHC

Cite This Study

RTHC-02349·https://rethinkthc.com/research/RTHC-02349

APA

Wilkerson, Jenny L; Schulze, David R; McMahon, Lance R. (2019). Tolerance and dependence to Δ9-tetrahydrocannabinol in rhesus monkeys: Activity assessments.. PloS one, 14(3), e0209947. https://doi.org/10.1371/journal.pone.0209947

MLA

Wilkerson, Jenny L, et al. "Tolerance and dependence to Δ9-tetrahydrocannabinol in rhesus monkeys: Activity assessments.." PloS one, 2019. https://doi.org/10.1371/journal.pone.0209947

RethinkTHC

RethinkTHC Research Database. "Tolerance and dependence to Δ9-tetrahydrocannabinol in rhesu..." RTHC-02349. Retrieved from https://rethinkthc.com/research/wilkerson-2019-tolerance-and-dependence-to

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.