Subcutaneous Methadone in Terminally Ill Patients

Abstract

Methadone has been found to be useful in pain uncontrolled by large doses of conventional opioids such as hydromorphone and morphine. While the subcutaneous route is effective and may afford cost-savings over the intravenous route in patients unable to take oral medication, its utility for the administration of methadone may be hampered by local toxicity, specifically erythema and induration. To examine the issue of limiting toxicity, we analyzed our inpatient hospice experience in six consecutive patients who received subcutaneous methadone for severe cancer pain. We confirm the high incidence of local toxicity, but note that the severity is subject to considerable individual variation. Furthermore, toxicity is uniformly manageable by site rotation and the use of dexamethasone infused concurrently with the methadone. We recommend that the infusion of subcutaneous methadone should be considered in the appropriate patients who can be closely monitored.

Uso de metadona en el anciano con dolor oncológico: una revisión sistemática

“…Esta vía de administración es igual de efectiva que la vía intravenosa pero plantea como inconvenientes reacciones irritativas en el punto de inyección. Para algunos autores este hecho obedece más a los excipientes que acompañan a la metadona que al principio activo 46 . Para disminuir estos efectos se recomienda rotar el punto de inserción y diluir la dosis de metadona 46 .…”

Methadone for relief of cancer pain: a review of pharmacokinetics, pharmacodynamics, drug interactions and protocols of administration

“…The pharmacokinetics is similar to that after oral dosing, demonstrating a rapid and extensive distribution phase and a slow elimination phase. The dose ratio for the rectal to the oral route is 1 : 1, whereas for intravenous or subcutaneous administration the dose is half of the oral dose [6,39,50,51]. Intravenous methadone produces a 23% higher concentration-to-dose ratio than oral dosing owing to the shunting of metabolism from the gut wall via CYP3A4 and avoidance in liver first-pass effects.…”

“…Intravenous methadone produces a 23% higher concentration-to-dose ratio than oral dosing owing to the shunting of metabolism from the gut wall via CYP3A4 and avoidance in liver first-pass effects. Subcutaneous methadone was initially associated with an adverse subcutaneous reaction, but toxicity is uniformly manageable by frequent site rotation and the use of either dexamethasone or hyaluronidase and by diluting the methadone to lower concentrations in solution [39, 50,51,52].…”

Antibiotiques par voie sous-cutanée chez la personne âgée

“….) et de préférer l'injection de médicaments iso-osmotiques dont le pH est compris entre 3,5 et 7,5[33]. Enfin, si l'injection SC d'antibiotique apparaît comme une voie d'administration parentérale simple à réaliser pour le personnel soignant, sûre et confortable pour le patient, le clinicien ne doit pas perdre de vue les 3 principales limites de cette technique.…”