From the Guidelines
Morphine should be avoided in patients with an estimated glomerular filtration rate (eGFR) below 15 mL/min/1.73m², as recommended by the most recent and highest quality study 1. At this level of kidney function, morphine and its active metabolites (particularly morphine-6-glucuronide) can accumulate in the body, leading to increased risk of serious adverse effects including excessive sedation, respiratory depression, and neurotoxicity. For patients with moderate kidney impairment (eGFR 30-60 mL/min/1.73m²), morphine can still be used but with caution, typically at reduced doses and with careful monitoring, as suggested by 1. Some key points to consider when using morphine in patients with kidney impairment include:
- Reducing the dose when GFR < 60 mL/min/1.73m², as recommended by 1
- Using with caution in people with GFR < 15 mL/min/1.73m², as recommended by 1
- Considering alternative opioids that are less affected by kidney function, such as fentanyl or hydromorphone, for pain management in patients with severe kidney impairment, as recommended by 1 and 1
- Significant dose reductions (50-75%), extended dosing intervals, and very close monitoring for signs of toxicity are essential to minimize risks if morphine must be used in patients with eGFR below 15 mL/min/1.73m². It's also important to note that other opioids, such as fentanyl and buprenorphine, are considered safer options in patients with chronic kidney disease stages 4 or 5 (estimated glomerular filtration rate <30 ml/min), as recommended by 1 and 1.
From the Research
Estimated Glomerular Filtration Rate (eGFR) and Morphine Use
- The use of morphine in patients with impaired renal function may be problematic due to pharmacokinetic and metabolic changes associated with renal dysfunction, which can increase the risk of side effects and overdosing 2.
- Morphine and codeine should be used with very caution and possibly avoided in renal failure/dialysis patients, while tramadol, hydromorphone, and oxycodone can be used with caution and close patient monitoring 2.
- There is limited and low-quality evidence to inform the safety and analgesic effect of opioid use in reduced renal function, with morphine being the opioid for which there is the most evidence available on safety and analgesic effect in the context of renal disease 3.
- The evidence for neurotoxicity due to morphine or hydromorphone use in renal impairment is of very low quality, with conflicting findings, and clinicians may consider using either morphine or hydromorphone in mild-to-moderate renal impairment while closely monitoring for neurotoxic effects 4.
Specific eGFR Values and Morphine Use
- A study on hydromorphone use in hospice patients with chronic kidney disease found that neuroexcitatory effects were more common in patients with lower eGFR values, with a strong and graded increase in neuroexcitatory effects with increasing quartile of dose or duration of hydromorphone 5.
- However, there is no specific eGFR value provided in the available evidence that indicates when morphine should be avoided.
- Nurses play a crucial role in ensuring safe medicines use for patients with impaired kidney function, including accurate drug dose adjustments and monitoring for potential drug-related complications 6.