Combo treatment relieves pain faster than morphine alone
The combination of low-dose methadone plus morphine leads to faster pain control relative to morphine alone, with no apparent difference in adverse effects, as shown in a study.
The study included 41 patients with cancer-related pain who received treatment in palliative setting and were initiating the third step of the analgesic ladder. These patients were randomized to receive methadone (2.5 mg/12 h) in combination with morphine or morphine alone. In both groups, morphine (5 mg) was used on as-needed basis to maintain pain intensity <4 and adjuvant in stable dose.
Results showed no significant difference in the number adjuvants, as well as in the dose of morphine used. However, pain intensity after 2 weeks of treatment was lower in the combination group than in the morphine monotherapy group; there was no statistically significant difference at other time points.
In terms of safety, adverse effects occurred similarly in the two treatment groups.
Opioids are a mainstay in the management of cancer-related pain. In patients with a poor analgesic response after opioid dose escalation, concomitant use of low doses of methadone has been shown to improve analgesia. Methadone is an opioid that exerts unique analgesic effects as a result of stimulation of regular mu-, kappa-, and delta-opioid receptors. It inhibits the NMDA receptor and affects the reuptake of serotonin and norepinephrine in the pain-modulating descending tracts in the medulla. [J Palliat Med 2020;23:226-232]