What are the contraindications for the use of Pyrroloquinoline Quinone (PQQ)?

Contraindications for Pyrroloquinoline Quinone (PQQ) Use

PQQ should not be used in patients with end-stage kidney disease (ESKD) on dialysis or those using interfering medications due to potential risk of serious hypoglycemic events.

Understanding PQQ and Its Contraindications

Pyrroloquinoline Quinone (PQQ) is a water-soluble quinone compound with strong antioxidant properties that functions as a cofactor for several bacterial dehydrogenases 1. While PQQ has been studied for various potential health benefits, there are important contraindications to consider:

Absolute Contraindications:

1. Patients with ESKD on dialysis:

   • PQQ in glucose monitoring systems (GDH-PQQ methodology) cannot distinguish between glucose and other sugars
   • Serious hypoglycemic events have been reported with GDH-PQQ-based glucose meters in dialysis patients 1
   • Falsely elevated glucose readings may occur, particularly in patients using peritoneal dialysis solutions containing icodextrin 1

2. Patients using interfering medications:

   • Avoid in patients using immunoglobulins, abatacept, or parenteral maltose/galactose/xylose solutions 1
   • These medications can cause dangerous interference with GDH-PQQ systems

Special Populations - Use with Caution:

1. Pregnant and lactating women:

   • The European Food Safety Authority (EFSA) evaluation specifically excluded pregnant and lactating women from their safety assessment 2
   • PQQ manufacturers typically recommend against use in these populations

2. Children and adolescents:

   • Limited safety data exists for pediatric populations
   • Most studies have focused on adult populations 3, 4

Clinical Evidence on PQQ Safety

The European Food Safety Authority (EFSA) has evaluated PQQ disodium salt (BioPQQ™) and concluded it is safe for healthy adults at a maximum proposed level of consumption of 20 mg/day, which corresponds to 0.29 mg/kg body weight per day for a 70-kg person 2. This assessment was based on:

• A 90-day repeated dose oral toxicity study establishing a no-observed-adverse-effect-level (NOAEL) of 100 mg/kg body weight per day
• A resulting margin of exposure of 344, which was deemed sufficient 2

However, this safety assessment specifically excluded pregnant and lactating women.

Monitoring Considerations

When using PQQ in eligible patients, consider:

• Monitoring serum cholesterol levels, as PQQ may affect LDL-cholesterol levels 3
• Being aware of potential interactions with medications that affect mitochondrial function, as PQQ influences mitochondrial biogenesis 4

Conclusion

While PQQ appears to have a favorable safety profile for most healthy adults at recommended doses (typically 20 mg/day), it is contraindicated in patients with ESKD on dialysis and those using certain interfering medications due to the risk of serious hypoglycemic events. Pregnant and lactating women should avoid PQQ supplementation until more safety data becomes available.

A 2022 study noted that "there is no contraindication" for PQQ supplementation 5, but this statement must be qualified with the specific contraindications identified in clinical guidelines regarding GDH-PQQ technology in glucose monitoring systems 1.