Impaired kidney function, or electrolyte imbalances, can contribute to malaise.
Urea 5.1 mmol/L (normal range 3.0-8.0 mmol/L)
Na 138 mmol/L (normal range 134-146 mmol/L)
K+ 4.1 mmol/L (normal range 3.4-5.0 mmol/L)
Cr 60 µmol/L (normal range 50-95 µmol/L for adult females)