Morphine Sulfate Oral Solution is available in three concentrations: 10 mg per 5 mL, 20 mg per 5 mL and 100 mg per 5 mL (20 mg/mL).
Take care when prescribing and administering Morphine Sulfate Oral Solution to avoid dosing errors due to confusion between different concentrations and between mg and mL, which could result in accidental overdose and death. Take care to ensure the proper dose is communicated and dispensed. When writing prescriptions, include both the total dose in mg and the total dose in volume. Always use the enclosed calibrated oral syringe when administering Morphine Sulfate Oral Solution 100 mg per 5 mL (20 mg/mL) to ensure the dose is measured and administered accurately.
Selection of patients for treatment with morphine sulfate should be governed by the same principles that apply to the use of similar opioid analgesics. Individualize treatment in every case, using non-opioid analgesics, opioids on an as needed basis and/or combination products, and chronic opioid therapy in a progressive plan of pain management such as outlined by the World Health Organization, the Agency for Healthcare Research and Quality, and the American Pain Society.
2.1 Individualization of Dosage
As with any opioid drug product, adjust the dosing regimen for each patient individually, taking into account the patient’s prior analgesic treatment experience. In the selection of the initial dose of morphine sulfate, give attention to the following:
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the total daily dose, potency and specific characteristics of the opioid the patient has been taking previously;
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the reliability of the relative potency estimate used to calculate the equivalent morphine sulfate dose needed;
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the patient’s degree of opioid tolerance;
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the general condition and medical status of the patient;
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concurrent medications;
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the type and severity of the patient’s pain;
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risk factors for abuse, addiction or diversion, including a prior history of abuse, addiction or diversion.
The following dosing recommendations, therefore, can only be considered suggested approaches to what is actually a series of clinical decisions over time in the management of the pain of each individual patient.
Continual re-evaluation of the patient receiving morphine sulfate is important, with special attention to the maintenance of pain control and the relative incidence of side effects associated with therapy. During chronic therapy, especially for non-cancer-related pain, periodically re-assess the continued need for the use of opioid analgesics.
During periods of changing analgesic requirements, including initial titration, frequent contact is recommended between physician, other members of the healthcare team, the patient, and the caregiver/family.
2.2 Initiation of Therapy in Opioid-Naïve Patients
Start patients who have not been receiving opioid analgesics on morphine sulfate in the following dosing range using Oral Solution, 10 mg per 5 mL or 20 mg per 5 mL strengths:
Morphine Sulfate Oral Solution: 10 to 20 mg every 4 hours as needed for pain.
Titrate the dose based upon the individual patient’s response to their initial dose of morphine sulfate. Adjust the dose to an acceptable level of analgesia taking into account the improvement in pain intensity and the tolerability of the morphine by the patient.
The 100 mg per 5 mL (20 mg/mL) oral solution formulation is for use in opioid-tolerant patients only who have already been receiving opioid therapy. Use this strength only for patients that have already been titrated to a stable analgesic regimen using lower strengths of morphine sulfate and who can benefit from use of a smaller volume of oral solution.
2.3 Conversion to Oral Morphine Sulfate
There is inter-patient variability in the potency of opioid drugs and opioid formulations. Therefore, a conservative approach is advised when determining the total daily dose of morphine sulfate. It is better to underestimate a patient’s 24-hour oral morphine sulfate dose and make available rescue medication than to overestimate the 24-hour oral morphine sulfate dose and manage an adverse experience of overdose.
Consider the following general points regarding opioid conversions.
Conversion From Parenteral Morphine to Oral Morphine Sulfate
For conversion from parenteral to oral morphine sulfate, anywhere from 3 to 6 mg of oral morphine sulfate may be required to provide pain relief equivalent to 1 mg of parenteral morphine.
Conversion From Parenteral Oral Non-Morphine Opioids to Oral Morphine Sulfate
In converting patients from other opioids to morphine sulfate, close observation and adjustment of dosage based upon the patient’s response to morphine sulfate is imperative. Physicians and other healthcare professionals are advised to refer to published relative potency information, keeping in mind that conversion ratios are only approximate.
Conversion From Controlled-Release Oral Morphine to Oral Morphine Sulfate
For a given dose, the same total amount of morphine sulfate is available from Morphine Sulfate Oral Solution, Morphine Sulfate Tablets, and controlled-release and extended-release morphine capsules. The extended duration of release of morphine sulfate from controlled-release tablets or extended-release tablets results in reduced maximum and increased minimum plasma morphine sulfate concentrations than with shorter acting morphine sulfate products. Conversion from oral solution or immediate-release tablets to the same total daily dose of controlled-release tablets or extended-release tablets could lead to excessive sedation at peak serum levels. Therefore, dosage adjustment with close observation is necessary.
2.4 Maintenance of Therapy
Continual re-evaluation of the patient receiving morphine sulfate is important, with special attention to the maintenance of pain control and the relative incidence of side effects associated with therapy. If the level of pain increases, effort should be made to identify the source of increased pain, while adjusting the dose as described above to decrease the level of pain. During chronic therapy, especially for non-cancer-related pain (or pain associated with other terminal illnesses), periodically reassess the continued need for the use of opioid analgesics.
2.5 Cessation of Therapy
When the patient no longer requires therapy with morphine sulfate, gradually taper the dose to prevent signs and symptoms of withdrawal in the physically dependent patient.
