Relief of pain: 2.5–10 mg IM, subcutaneously, or PO every 8–12 hr as necessary. IM route is preferred to subcutaneous for repeated doses (subcutaneous use may cause local irritation). Individualize dosage; patients with excessively severe pain and those who have become tolerant to the analgesic effect of opioids may need higher dosage.

Detoxification: Initially, 20–30 mg PO or parenteral; PO preferred. Increase dose to suppress withdrawal signs. 40 mg/day in single or divided doses is usually an adequate stabilizing dose for those physically dependent on high doses. Continue stabilizing doses for 2–3 days, then gradually decrease dosage every day or every 2 days. A daily reduction of 20% of the total dose may be tolerated. Provide sufficient dosage to keep withdrawal symptoms at tolerable level. Treatment should not exceed 21 days and may not be repeated earlier than 4 wk after completion of previous course. Detoxification treatment continued longer than 21 days becomes maintenance treatment, which may be undertaken only by approved programs (addicts hospitalized for other
medical conditions may receive methadone maintenance treatment).

Maintenance treatment: For patients who had been heavy heroin users up until hospital admission, initial dose of 20 mg PO 4–8 hr after heroin is stopped or 40 mg in a single dose PO. For patients with little or no opioid tolerance, half this dose may suffice. Dosage should suppress withdrawal symptoms but not produce acute opioid effects of sedation, respiratory depression. Give additional 10-mg doses if needed to suppress withdrawal syndrome. Adjust dosage, up to 120 mg/day.