【藥品性質提示】 根據 2019 AGS Beers Criteria，本藥品為【潛在不適當用藥 (PIM)】，不建議用於有骨折風險之老年人(除非用於急性止痛)。 #高警訊藥品

鴉片類止痛 Relief of visceral pain, preanesthetic medication

Opioid Analgesic
Binds to opioid receptors in the CNS, causing inhibition of ascending pain pathways, altering the perception of and response to pain; produces generalized CNS depression.

1. Onset of action: ~30 min
2. Duration: 4 hrs
3. Metabolism: Morphine is inactivated in the liver, primarily by conjugation to morphine-6-glucuronide (active) and morphine-3-glucuronide (inactive or antagonistic).
4. Excretion: Mostly excreted in urine; Accumulation of morphine-6-glucuronide might cause toxicity with renal insufficiency.

1. Hypersensitivity to morphine or any component of the formulation
2. Severe respiratory depression (without resuscitative equipment); acute or severe asthma
3. Known or suspected paralytic ileus, acute pancreatitis

Prolonged use of morphine during pregnancy can result in neonatal opioid withdrawal syndrome, which may be life-threatening.

1. Nonopioid analgesics are preferred for breastfeeding females who require pain control peripartum or for surgery outside of the postpartum period.
2. When opioids are needed in breastfeeding women, the lowest effective dose for the shortest duration of time should be used.

Respiratory and circulatory depression, constipation, miosis, drowsiness, bradycardia, hypotension, sedation, dizziness, nausea, vomiting, sweating

Acute pain in opioid-naive patients:
1. Initial 10 mg every 4 hours as needed; if pain is not relieved, may increase dose as tolerated
2. May give up to 30 mg every 4 hours as needed for severe, acute pain in hospitalized patients at low risk for respiratory depression
Chronic pain:
1. Initial 5 to 30 mg every 4 hours as needed
2. For chronic noncancer pain: most patients will have pain control with initial doses <50 mg/day; may increase the dose slowly in increments of no more than 25% to 50% of the total daily dose
3. For chronic cancer pain: may increase the fixed scheduled dose by 30% to 100% of the total dose taken in the prior 24-hour period

Acute pain: (Infants >6 months, Children, and Adolescents)
1. Patient weight <50 kg: 0.2 to 0.5 mg/kg/dose every 3 to 4 hours as needed; usual initial maximum dose: 15 to 20 mg
2. Patient weight ≥50 kg: 15 to 20 mg every 3 to 4 hours as needed
Chronic pain:
1. Weight-directed dosing: 0.3 to 0.6 mg/kg/dose every 12 hours
2. Alternate dosing (fixed dosing):
(1) Patient weight 20 to <35 kg: 10 to 15 mg every 8 to 12 hours
(2) Patient weight 35 to <50 kg: 15 to 30 mg every 8 to 12 hours
(3) Patient weight ≥50 kg: 30 to 45 mg every 8 to 12 hours

1. CrCl ≥60 mL/minute: No dosage adjustment necessary
2. CrCl 30 to <60 mL/minute: Administer 50% to 75% of usual initial dose; may also consider extending dose interval
3. CrCl 15 to <30 mL/minute: Avoid use. If necessary, administer 25% to 50% of usual initial dose; may also consider extending dose interval
4. CrCl <15 mL/minute, Hemodialysis: Avoid use
5. CRRT, PIRRT: Other opioids are preferred

There are no dosage adjustments provided in the manufacturer's labeling. In cirrhosis, increases in half-life and AUC suggest dosage adjustment required.