Clinical Textbook of Addictive Disorders 3rd ed - R. Frances, S. Miller, A. Mack (Guilford, 2005) WW

TABLE 17.5. Opioid AsnalgesicsEquianalgesic Half-lifedoses a (hours)Peak effect(hours)Duration ofeffect (hours) CommentssPure agonists (morphine-like)Morphine 10 i.m. 2–3 0.5–1 3–6 Standard comparior for opioids.20–60 p.o. b 2–3 1.5–2 4–7 Multiple routes available.Controlled-release morphine 20–60 p.o. b 2–3 3–4 8–12Sustained-release morphine 20–60 p.o. b 2–3 4–6 24Hydromorphone 1.5 i.m. 2–3 0.5–1 3–4 Multiple routes available.7.5 p.o. 2–3 1–2 3–4Oxycodone 20–30 p.o. 2–3 1 3–6 Combined with aspirin or acetaminophen for moderate pain;available orally without coanalgesic for severe pain.Controlled-release oxycodone 20–30 2–3 3–4 8–12Oxymorphone 1 i.m. — 0.5–1 3–6 No oral formulation.10 p.r. — 1.5–3 4–6Meperidine 75 i.m. 2–3 0.5–1 3–4 More CNS excitation than with other opioids. Not300 p.o. 2–3 1–2 3–6preferred for chronic pain due to potential toxicity.Heroin 5 i.m. 0.5 0.5–1 4–5 Analgesic action due to metabolites, predominantly inmorphine; not available in United States.Levorphanol 2 i.m. 12–15 0.5–1 3–6 Long half-life; accumulation occurs after starting or4 p.o.increasing dose.Methadone 10 i.m. 12– >150 0.5–1.5 4–8 Risk of delayed toxicity due to accumulation; useful to start20 p.o.to start dosing on p.r.n. basis, with close monitoring.Codeine 130 i.m. 2–3 1.5–2 3–6 Usually combined with nonopioid.200 p.o.382