What are the dosages to switch a patient from heroin to methadone (Dolophine) for opioid substitution therapy?

From the Guidelines

Methadone induction must be conducted under medical supervision due to significant risks including respiratory depression and death if improperly dosed. The transition from heroin to methadone requires careful evaluation of the patient's opioid tolerance, medical history, concurrent medications, and other individual factors. Generally, treatment begins with a conservative initial dose (typically 20-30mg) followed by careful titration based on the patient's response, with close monitoring for withdrawal symptoms and side effects, as noted in studies such as 1. Dosing adjustments typically occur over days to weeks until a stable maintenance dose is achieved. This process should only be conducted in appropriate clinical settings such as specialized addiction treatment centers or hospitals with protocols for opioid replacement therapy. The goal is to prevent withdrawal symptoms while avoiding over-sedation, with eventual stabilization on a dose that blocks cravings and prevents withdrawal for 24 hours. Due to methadone's long half-life and potential for accumulation, rapid dose escalation can be dangerous, as highlighted in guidelines like 1. Some key considerations include:

• Initial screening with electrocardiogram to identify heart rate corrected QT (QTc) prolongation for all patients on methadone, with interval follow-up with dose changes, as recommended by 1.
• The splitting of methadone into 6- to 8-hour doses to lengthen the active analgesic effects of methadone with the goal of continuous pain control, as suggested by 1.
• Methadone should not be the first choice for an ER/LA opioid, and only clinicians who are familiar with methadone’s unique risk profile and who are prepared to educate and closely monitor their patients should consider prescribing methadone for pain, as advised by 1. It's crucial to follow the most recent and highest quality guidelines, such as those from 1, to ensure safe and effective treatment.

From the FDA Drug Label

The initial methadone dose should be administered, under supervision, when there are no signs of sedation or intoxication, and the patient shows symptoms of withdrawal. Initially, a single dose of 20 to 30 mg of methadone will often be sufficient to suppress withdrawal symptoms The initial dose should not exceed 30 mg. If same-day dosing adjustments are to be made, the patient should be asked to wait 2 to 4 hours for further evaluation, when peak levels have been reached. An additional 5 to 10 mg of methadone may be provided if withdrawal symptoms have not been suppressed or if symptoms reappear The total daily dose of methadone on the first day of treatment should not ordinarily exceed 40 mg. For Short-term Detoxification For patients preferring a brief course of stabilization followed by a period of medically supervised withdrawal, it is generally recommended that the patient be titrated to a total daily dose of about 40 mg in divided doses to achieve an adequate stabilizing level For Maintenance Treatment Patients in maintenance treatment should be titrated to a dose at which opioid symptoms are prevented for 24 hours, drug hunger or craving is reduced, the euphoric effects of self-administered opioids are blocked or attenuated, and the patient is tolerant to the sedative effects of methadone. Most commonly, clinical stability is achieved at doses between 80 to 120 mg/day

The dosages to switch a patient from heroin to methadone are as follows:

• Initial dose: 20 to 30 mg of methadone, not to exceed 30 mg, to suppress withdrawal symptoms.
• Same-day dosing adjustments: Wait 2 to 4 hours, then add 5 to 10 mg if symptoms persist.
• Total daily dose on the first day: Not to exceed 40 mg.
• Short-term detoxification: Titrate to 40 mg in divided doses.
• Maintenance treatment: Titrate to a dose between 80 to 120 mg/day to prevent opioid symptoms and reduce cravings 2.

From the Research

Switching from Heroin to Methadone

The process of switching a patient from heroin to methadone involves careful consideration of the patient's individual needs and medical history.

• The initial step is to assess the patient's current opioid use and determine the equivalent methadone dose.
• However, the provided studies do not offer specific guidance on the dosages for switching a patient from heroin to methadone 3, 4, 5, 6, 7.
• Study 6 discusses the comparison of two switching strategies from morphine/oxycodone to methadone, but it does not provide information on switching from heroin to methadone.
• It is essential to note that methadone dosing should be individualized and monitored closely to ensure patient safety and effectiveness of treatment.

Methadone Dosing Considerations

When determining methadone dosing, several factors should be considered, including:

• The patient's previous opioid use and tolerance
• The presence of any medical or psychiatric comorbidities
• The risk of overdose or respiratory depression
• However, the provided studies do not offer specific dosing recommendations for switching from heroin to methadone 3, 4, 5, 6, 7.

Monitoring and Follow-up

Close monitoring and follow-up are crucial when switching a patient from heroin to methadone.

• Patients should be closely observed for signs of overdose or respiratory depression, particularly during the initial stages of treatment 6, 7.
• Regular assessments of the patient's response to methadone and adjustments to the dose as needed are essential to ensure effective treatment and minimize the risk of adverse effects.