Does Kratom (Mitragyna speciosa) cause nephrotoxicity or impaired renal function?

Kratom and Renal Effects

Kratom (Mitragyna speciosa) can cause nephrotoxicity and impaired renal function, particularly with regular long-term use, manifesting primarily as proteinuria which may indicate early kidney injury. 1

Evidence of Renal Effects

• Regular consumption of kratom over prolonged periods (average of eleven years) has been associated with proteinuria, suggesting early-stage kidney injury 1
• Albumin is the primary protein excreted in kratom users' urine, with elevated protein-to-creatinine ratios compared to healthy controls 1
• Acute renal insufficiency has been reported in cases of kratom consumption, though some cases may involve adulterated products 2

Mechanisms of Renal Toxicity

• The exact nephrotoxic mechanism of kratom is not fully elucidated, but appears similar to other substances that cause drug-induced nephropathy 3
• Kratom contains over 40 alkaloids that bind to opioid receptors, which may contribute to its effects on renal function 4
• Mitragynine, the primary active alkaloid in kratom, may have direct or indirect effects on renal tubular function 1

Risk Factors for Kidney Injury

• Long-term regular use appears to increase risk of renal effects 1
• Concurrent use of other nephrotoxic substances may potentiate kidney damage 2
• Adulteration of kratom products with other substances (including opioids) may contribute to renal toxicity 2
• Higher doses and more frequent use patterns likely increase risk of adverse renal outcomes 3

Clinical Manifestations

• Proteinuria is the most common laboratory finding in regular kratom users 1
• Clinical symptoms may include:
  • Flank pain 2
  • Nausea and vomiting 3
  • Polyuria 3
• Laboratory abnormalities may include:
  • Elevated serum creatinine 2
  • Elevated protein-to-creatinine ratio 1
  • Presence of albumin in urine 1

Monitoring Recommendations

• For individuals using kratom, especially long-term users, monitoring of renal function is advisable 1
• Baseline assessment of renal function and regular follow-up is prudent 3
• Urinalysis to detect proteinuria may help identify early renal effects 1

Management of Kratom-Associated Renal Effects

• Discontinuation of kratom use is the primary intervention for suspected kratom-induced renal effects 2
• Supportive care is typically sufficient for recovery of renal function 2
• Monitoring of renal parameters until normalization is recommended 2

Important Considerations

• Kratom products are unregulated and non-standardized, increasing risk of adulteration 2
• Testing for adulterants should be considered in cases of unexplained renal dysfunction in kratom users 2
• The benefits of kratom use may not outweigh its potential toxicity and risks to renal function 3

While more research is needed to fully characterize kratom's effects on kidney function, the available evidence suggests caution is warranted, particularly with long-term use, due to the potential for nephrotoxicity manifesting primarily as proteinuria and potentially progressing to more severe renal impairment.