Creatinine 1.6 mg/dL (141 µmol/L): Is It High?

A serum creatinine of 1.6 mg/dL is 141.44 µmol/L. It is 0.3 mg/dL, or 23%, above the upper limit for men (0.7 to 1.3 mg/dL), and 0.5 mg/dL, or 45%, above the upper limit for women (0.6 to 1.1 mg/dL). At age 50 it gives a CKD-EPI 2021 eGFR of 52 (G3a) for a man and 39 (G3b) for a woman. It is above the usual range for both sexes; how much that matters depends on age, muscle mass and the trend.

1.6 mg/dL in µmol/L and mmol/L

Multiply by 88.4: 1.6 × 88.4 = 141.44 µmol/L, which most laboratories round to 141 µmol/L, or 0.141 mmol/L. Going back, 141 ÷ 88.4 = 1.6 mg/dL, and any result from 138 to 145 µmol/L rounds to 1.6 mg/dL. The creatinine unit converter handles other results.

eGFR at a Creatinine of 1.6 mg/dL by Age and Sex

With the race-free CKD-EPI 2021 equation, 1.6 mg/dL (141 µmol/L) gives:

For a man, the eGFR drops below 60 from about age 29 and below 45 from about age 76. For a woman, the eGFR is below 60 at every adult age, drops below 45 from about age 29 and below 30 from about age 96. An eGFR below 60 for more than three months meets the KDIGO definition of chronic kidney disease.

What these results mean: eGFR 60, eGFR 55, eGFR 50, eGFR 45, eGFR 40, eGFR 35, eGFR 30.

Older Equations on Earlier Reports

Some laboratories still report CKD-EPI 2009 or MDRD, so an older result may not match. For a 60-year-old at 1.6 mg/dL the three equations differ by up to 5 points:

See MDRD vs CKD-EPI for why the numbers differ.

Creatinine Clearance at 1.6 mg/dL: Four Example Patients

Drug doses are usually checked against Cockcroft-Gault creatinine clearance, which also uses weight. Our dosing-weight rule uses actual weight below ideal body weight (IBW), IBW up to 30% above it, and adjusted body weight (AjBW) beyond that.

At 1.6 mg/dL, CrCl runs from 20.5 mL/min (woman, 82) to 66.1 mL/min (man, 55). 1 of 4 is below 30 mL/min, where 22 drugs in our renal dosing registry have a cutoff, and 2 are below 50, where 16 do. The formula assumes a stable creatinine.

Which Dosing Lines 1.6 mg/dL Crosses

In our registry, 9 drugs change at 60, 16 drugs change at 50, 22 drugs change at 30, and 8 drugs change at 15 mL/min of creatinine clearance. The list shows where each example adult stands at 1.6 mg/dL, using the same Cockcroft-Gault engine and weights as the table above:

• Man aged 40, 80 kg: 63.4 mL/min, above all four lines. Reaches 60 mL/min at about 1.69 mg/dL.
• Woman aged 65, 62 kg: 30.3 mL/min, below 60 and 50. Reaches 30 mL/min at about 1.61 mg/dL.
• Woman aged 82, 48 kg: 20.5 mL/min, below 60, 50 and 30. Reaches 15 mL/min at about 2.19 mg/dL.
• Man aged 55, 118 kg: 66.1 mL/min, above all four lines. Reaches 60 mL/min at about 1.76 mg/dL.

No example adult crosses a new line between 1.5 and 1.6 mg/dL. The next line any of them meets is 30 mL/min, for the woman aged 65, at about 1.61 mg/dL. At 30 mL/min, 22 drugs in our registry change, including alogliptin, amoxicillin-clavulanate and aztreonam.

In the eGFR table, 12 of 12 results are below 60, up from 10 at 1.5 mg/dL, and none are below 30.

Is 1.6 mg/dL High for You?

1.6 mg/dL is mildly above the usual range, and all 12 table results are below 60, spanning categories G3a to G3b. It often reflects mildly to moderately reduced filtration, but temporary factors can produce it too, so the test is usually repeated before conclusions are drawn.

At 1.6 mg/dL, a short-lived cause is worth ruling out first. Dehydration, intense exercise, creatine supplements and drugs that block tubular secretion, such as trimethoprim, can raise creatinine without changing filtration. See causes of high creatinine.

When a Result of 1.6 mg/dL Needs Prompt Attention

If 1.6 mg/dL is your usual (baseline) value, a rise to 1.9 mg/dL within 48 hours, or to 2.4 mg/dL within 7 days, meets the KDIGO creatinine criteria for acute kidney injury and should be assessed promptly. So should much less urine, swelling, confusion or breathlessness.

• Compare the result with earlier ones: stable and rising mean different things.
• Ask for your eGFR and, if you take regular medicines, your creatinine clearance.
• Mention recent illness, new medicines, supplements or contrast scans.

There is no quick "flush": how to lower creatinine covers what helps, with your clinician.

Nearby Creatinine Results

• Lower result: Creatinine 1.5 mg/dL (133 µmol/L)
• Higher result: Creatinine 1.7 mg/dL (150 µmol/L)

Or browse all creatinine results.