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What are the time-line differences for the Opioid Withdrawal Severity Scale (OWSS)?
Date created:
Monday, December 8, 2025
Opioid Withdrawal Reference Table
1. FENTANYL (illicit inhaled/smoked/IV equivalent patterns)
Morphine Equivalent Dose¹ : 1 mcg/hr of Fentanyl is 2.4 mg/day of Morphine
Parameter | Typical Range |
Onset | 6–12 hrs |
Peak | 24–48 hrs |
Duration | 5–7 days |
Notes | Fast, spiking, unpredictable |

2. HYDROMORPHONE – Immediate Release (Dilaudid)
Morphine Equivalent Dose
