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Pharmacokinetic Reference?
Date created:
Thursday, December 11, 2025
Opioid Pharmacokinetic 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 | Seconds to 5 min |
Peak Effect | 5–15 min |
Duration | 1–3 hrs |
Half-life (t½) | ~3–7 hrs |
Elimination | ~15–35 hrs |
2. HYDROMORPHONE – Immediate Release (Dilaudid)
Morphine Equivalent Dose¹ : 1 mg/day of Hydromorphone is 5 mg/day of Morphine
Parameter | Typical Range |
Onset | 10–20 min |
Peak Effect | 30–60 min |
Duration | 3–6 hrs |
Half-life (t½) | 2–3 hrs |
Elimination | ~10–15 hrs |
3. OXYCODONE – Immediate Release (Percocet)
Morphine Equivalent Dose¹ : 1 mg/day of Oxycodone is 1.5 mg/day of Morphine
Parameter | Typical Range |
Onset | 10–30 min |
Peak Effect | 60–90 min |
Duration | 3–6 hrs |
Half-life (t½) | –3-4.5 hrs |
Elimination | ~15–22 hrs |
4. MORPHINE – Immediate Release (Mosinar / Statec)
Morphine Equivalent Dose¹ : 1 mg/day of Morphine is 1 mg/day of Morphine
Parameter | Typical Range |
Onset | 30–60 min |
Peak Effect | 60–90 min |
Duration | 3–6 hrs |
Half-life (t½) | 2–4 hrs |
Elimination | ~10–20 hrs |
5. CODEINE – Immediate Release (Tylenol #2,#3,#4)
Morphine Equivalent Dose¹ : 1 mg/day of Codeine is 0.15 mg/day of Morphine
Parameter | Typical Range |
Onset | 30–60 min |
Peak Effect | 1–2 hrs |
Duration | 3–6 hrs |
Half-life (t½) | 2.5–3.5 hrs |
Elimination | ~12–18 hrs |
6. METHADONE / METHADOSE (0.1mg/ml while Methadose is commonly 1mg/ml)
(Methadone is extremely slow to eliminate.)
Morphine Equivalent Dose¹ : 1 mg/day of Methadone/Methadose is 4.7 mg/day of Morphine
Parameter | Typical Range |
Onset | 30–60 min |
Peak Effect | 2–4 hrs |
Duration | 24–36 hrs (sometimes longer) |
Half-life (t½) | 8–59 hrs (huge variation; commonly 24–36 hrs) |
Elimination | 40–300 hrs depending on metabolism |
7. MORPHINE – Extended Release (MS Contin) (note: uses timed-release coated beads over 8–12 hours)
Morphine Equivalent Dose¹ : 1 mg/day of Morphine is 1 mg/day of Morphine
Parameter | Typical Range |
Onset | 30–90 min |
Peak Effect | 2–4 hrs (controlled-release curves vary) |
Duration | 8–12 hrs |
Half-life (t½) | 2–4 hrs (same drug; slower delivery) |
Elimination | ~10–20 hrs |
8. MORPHINE – Extended Release (Kadian / M-Eslon / SROM)
(Kadian’s long duration comes from the beads, not the drug half-life.)
Morphine Equivalent Dose¹ : 1 mg/day of Morphine is 1 mg/day of Morphine
Parameter | Typical Range |
Onset | 45–90 min |
Peak Effect | 2–4 hrs |
Duration | 12–24 hrs (depends on formulation) |
Half-life (t½) | 2–4 hrs |
Elimination | ~10–20 hrs |
9. OXYCODONE – Controlled Release (OxyContin)
(uses timed-release coated tablets over 8–12 hours)
Morphine Equivalent Dose¹ : 1 mg/day of Oxycodone is 1.5 mg/day of Morphine
Parameter | Typical Range |
Onset | 30–60 min |
Peak Effect | 3–4 hrs |
Duration | 8–12 hrs (sometimes 12+) |
Half-life (t½) | ~4–5 hrs (same drug; release is slower) |
Elimination | ~20–25 hrs |
10. HYDROMORPHONE – Extended Release (Hydromorph Contin)
(uses timed-release coated beads over 8–12 hours)
Morphine Equivalent Dose¹ : 1 mg/day of Hydromorphone is 5 mg/day of Morphine
Parameter | Typical Range |
Onset | 30–90 min |
Peak Effect | 6–9 hrs (slow-release curve) |
Duration | 12–24 hrs |
Half-life (t½) | 2–3 hrs |
Elimination | ~10–15 hrs |
11. CODEINE – Extended Release (Codeine Contin)
(Used far less now, but exists.)
Morphine Equivalent Dose¹ : 1 mg/day of Codeine is 0.15 mg/day of Morphine
Parameter | Typical Range |
Onset | 60–90 min |
Peak Effect | 3–4 hrs |
Duration | 8–12 hrs |
Half-life (t½) | 2.5–3.5 hrs |
Elimination | ~12–18 hrs |
¹ Morphine equivalency calculator, source: https://northwestpainguidance.org/opioidmedcalculator/
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