Pain
Morphine
Morphine is the most commonly used opioid for moderate and severe pain in pediatric palliative care.
Morphine is an opioid receptor agonist that binds and activates the mu opioid receptors in the central nervous system.
Almost all morphine is converted by hepatic metabolism to the 3-and 6- glucuronide metabolites (M3G and M6G) (2).
Morphine elimination is renal, so caution needs to be taken in patients with renal failure as metabolites can accumulate in blood.
Different administration routes can be used: oral, sublingual, subcutaneous, intravenous, rectal, intrathecal and epidural.
Table 1. Adapted from Dosing Guideline for Morphine in Children, (H.Siden) (3)
Route |
Younger Child < 50 kg |
Older Child > 50 kg |
Comments |
Response Time |
Duration of action |
Oral (PO) |
0.15-0.3 mg/kg q 4 hr |
5-30 mg q4h |
|
45-60 min |
|
Extended release |
|
|
Convert from short acting |
|
12 hrs is usual |
Sub- cutaneous (SC) |
0.05-0.1 mg/kg q 4h |
5-10 mg q 4 h |
|
|
|
IV intermittent |
|
5-10 mg q 4 h |
|
10 min |
|
IV/SC infusion |
10-20 mcg/kg/hr are usual starting doses in opioid naive patients |
|
Titrate upward-provide with basal rate and breakthrough-patient or nurse PCA |
|
|
