What is the lactate/pyruvate ratio used for?

The ratio indirectly reflects the chemical balance inside cells. Specialists use it, together with other tests, to help interpret a raised lactate and to look for clues to inherited disorders of energy metabolism, such as mitochondrial disease.

Why is the collection so specific?

Pyruvate breaks down quickly and lactate rises artificially with a tourniquet, a clenched fist or exertion. Quest therefore requires a draw without a tourniquet and immediate mixing of the blood with ice-cold perchloric acid, then freezing the filtrate.

Yes. Quest requires a fasting sample. Do not eat for at least 8 hours beforehand; water is fine. Also avoid exercise for several hours before the draw.

Can medications affect the result?

Some medicines, including metformin, can raise lactate. Keep taking your medications as prescribed and tell the clinician interpreting the test what you take.

How fast will I get results?

Quest typically reports this test the day after the sample reaches the lab. Results appear in your private JustLabs dashboard.

Can I use my FSA or HSA, and does insurance cover it?

JustLabs is a cash-pay service: the test is $82, plus one flat $18 Lab & Physician Order Fee per order, and no insurance claim is filed. Lab tests are generally eligible for FSA and HSA funds, and JustLabs provides an itemized receipt you can submit, but check with your plan administrator to confirm.

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🔥 Metabolic

Lactate and Pyruvate Blood Test (with Lactate/Pyruvate Ratio)

Lactate/Pyruvate

Measures lactate and pyruvate in the same fasting blood sample and reports the ratio between them. Clinicians use it, together with other tests, when they suspect a mitochondrial or other inherited disorder of energy metabolism.

Lactate and pyruvate are two closely linked products of the way cells break down glucose for energy. When cells cannot use oxygen normally, or when a step in energy metabolism is blocked, lactate builds up. Measuring pyruvate at the same time lets the lab calculate the lactate-to-pyruvate ratio, which indirectly reflects the chemical balance inside cells and helps a specialist judge where a problem might lie.

This test is mostly used in the evaluation of suspected mitochondrial disease, a group of inherited conditions in which the cell's energy-producing machinery does not work properly. It is one piece of a broader work-up, not a diagnosis: many people with mitochondrial disease have normal lactate and pyruvate between episodes, and a raised lactate has many other causes.

The biggest challenge with this test is the sample itself. Pyruvate is unstable, and lactate rises artificially with a tight tourniquet, a clenched fist, struggling or recent exercise. Quest therefore requires a fasting patient, a draw without a tourniquet, and immediate mixing of the blood with ice-cold perchloric acid at the collection site.

Because the collection is unusual, this test is best ordered in coordination with the clinician or specialist who will interpret it.

Price

$82

All-in

$100

incl. $18 lab & physician fee

Results

1 business days

Fasting

8+ hrs

What's Measured

Lactic Acid

Pyruvic Acid (Pyruvate)

Lactate/Pyruvate Ratio

What This Test Measures

Lactic acid (lactate) and pyruvic acid (pyruvate) in a deproteinized whole-blood filtrate, measured by enzymatic methods, and the lactate/pyruvate ratio calculated from the two.

Who Should Consider This Test

People being evaluated by a clinician or specialist for a suspected mitochondrial disorder or another inherited disorder of energy metabolism, for example because of unexplained muscle weakness, exercise intolerance or a raised lactate on earlier testing. It is not a general wellness or fitness test.

Health Insights

Conditions Screened

Suspected mitochondrial disordersInherited disorders of pyruvate metabolismLactic acidosis (evaluation)

Related Symptoms

Exercise intoleranceUnexplained muscle weaknessMuscle pain or cramps with exertionUnexplained fatiguePreviously raised lactate

When to Get Tested

When your clinician or specialist requests it as part of a metabolic work-up, typically after a raised lactate or symptoms that suggest an energy-metabolism disorder. Test in a fasting, rested state: avoid exercise for several hours beforehand, because exercise raises lactate temporarily.

Fasting Required

This test requires fasting for accurate results. Please follow these instructions:

Do not eat or drink anything except water for 8-12 hours before your blood draw.
Water is allowed and encouraged - stay hydrated!
Schedule your lab visit in the morning for convenience.
Continue taking any prescribed medications unless advised otherwise by your doctor.

How long to fast, and what breaks a fast →

Understanding Your Results

Quest reports lactic acid and pyruvic acid in mg/dL plus the lactate/pyruvate ratio; Quest's reference ranges for this test are 9.0-16.0 mg/dL for lactic acid, 0.30-1.50 mg/dL for pyruvate and 10-20 for the ratio. A raised lactate can come from reduced oxygen delivery (for example heart or lung disease, anemia or severe infection), liver or kidney disease, uncontrolled diabetes, some medicines such as metformin, strenuous exercise, inherited mitochondrial disorders, or simply from the way the sample was collected. The ratio helps a specialist interpret the pattern, but normal results do not rule out mitochondrial disease and abnormal results need confirmation and further testing. Review your results with the clinician who ordered the evaluation.

What to Expect

After placing your order, we send it straight to Quest Diagnostics — there is no consent form to sign and no partner email to wait for. Your requisition is usually ready to download from your dashboard within about an hour, and you can book your blood draw at any Quest Diagnostics location.

The blood draw typically takes just a few minutes. Results are usually available within 1 business days and will appear in your secure JustLabs dashboard.

Our results include reference ranges and easy-to-understand indicators showing whether your values are within normal limits.

How much does the Lactate/Pyruvate test cost?

The Lactate/Pyruvate test costs $82 at JustLabs — $100 all-in, since the $18 lab & physician order fee is charged once per order, however many tests you add. The price is fixed before your blood draw; no insurance or doctor visit needed.