# Evolution of Analgesic Tolerance With Opioids

> **NCT00275249** · NA · COMPLETED · sponsor: **University of California, San Francisco** · enrollment: 60 (—)

## Conditions studied

- Chronic Pain

## Interventions

- **DRUG:** levorphanol

## Key facts

- **NCT ID:** NCT00275249
- **Lead sponsor:** University of California, San Francisco
- **Sponsor class:** OTHER
- **Phase:** NA
- **Study type:** INTERVENTIONAL
- **Status:** COMPLETED
- **Start date:** 2001-03
- **Primary completion:** 2004-10
- **Final completion:** 2005-12
- **Target enrollment:** 60 (—)
- **Last updated:** 2011-04-14


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT00275249

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT00275249, "Evolution of Analgesic Tolerance With Opioids". Retrieved via AI Analytics 2026-09-17 from https://api.ai-analytics.org/clinical/NCT00275249. Licensed CC0.

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