Lab test explainer

Glucose

A glucose result tells you how much glucose was in the blood sample when it was collected. Whether you had fasted changes what the number means.

Printed on reports as: Glucose · GLU · Blood sugar · Fasting plasma glucose (FPG) · Random glucose

What it measures

The amount of glucose in a blood sample at collection. A fasting result and a random result reflect different collection circumstances.

Why it is checked

To help screen for or evaluate a glucose problem, investigate symptoms, or monitor diabetes or treatment. Glucose also appears on routine chemistry panels, such as a basic or comprehensive metabolic panel.

What can affect the result
  • Fasting status. A fasting test follows at least eight hours without food; a random test can happen at any time, even after eating. Check whether fasting was requested and whether it occurred.
  • Medicines. Some can raise glucose (for example steroids, antipsychotics, beta-blockers and statins), and some can lower it (for example ACE inhibitors and quinolone antibiotics).
  • Health conditions and stress on the body, such as serious illness, trauma, surgery, and some hormone conditions.
  • For people with diabetes, low readings can follow eating too little after diabetes medicine or unusually high physical activity.
Read alongside

A1C provides a longer view. Home readings or continuous glucose monitoring may add context when they are already part of a clinician's care plan. Keep the test type, unit and timing with each result.

Peptide connections

Two prescribing labels discuss glucose. They apply to different products and different patient populations, and neither is a general pretreatment test.

Prescribing informationVerified 2026-11-06

Wegovy · semaglutide

In patients with diabetes mellitus, monitor blood glucose prior to starting WEGOVY and during WEGOVY treatment.
Section 2.1 (Important Monitoring and Administration Instructions); the same instruction appears in Section 5.4 (Hypoglycemia).
Role of the marker
Monitoring instruction
Formulation
Injection and tablets (one combined label)
Jurisdiction
United States (FDA-approved labeling on DailyMed)
Population in the source
Patients with diabetes mellitus (for the glucose-monitoring instruction)
Indication and status
Reduce major adverse cardiovascular events in adults with established cardiovascular disease and obesity or overweight; reduce excess body weight and maintain weight loss; the injection also has an indication for noncirrhotic MASH with moderate to advanced liver fibrosis in adults. See the label for the full indications and age groups.
What this does not establish
The instruction applies to patients with diabetes. It does not set a testing schedule or a target, and it does not describe a test everyone must have before treatment.

Question to bring: “Do I need a glucose monitoring plan, and what should I do if a reading concerns me?”

Prescribing informationVerified 2026-11-06

Egrifta WR · tesamorelin

Evaluate glucose status prior to initiating EGRIFTA WR. Monitor all patients treated with EGRIFTA WR periodically to diagnose those who develop impaired glucose tolerance.
Section 5.4 (Glucose Intolerance or Diabetes Mellitus)
Role of the marker
Monitoring instruction
Formulation
For injection, 11.6 mg/vial kit
Jurisdiction
United States (FDA-approved labeling on DailyMed)
Population in the source
HIV-infected adult patients with lipodystrophy
Indication and status
Reduction of excess abdominal fat in HIV-infected adult patients with lipodystrophy. The label states it is not indicated for weight loss management and that long-term cardiovascular safety has not been established.
What this does not establish
The label does not give a testing interval in this section. The monitoring instruction does not make a person eligible for the product.

Question to bring: “Which tests are for safety, and how will we assess whether treatment is helping?”

A connection describes what a source says about monitoring. It does not show that a result makes anyone eligible for, or a candidate for, a medication.

Questions for your healthcare team

“Was this interpreted as a fasting or random result, and does that affect what we do next?”

Add it to the appointment worksheet →

Sources and review status

  • Medicine and condition examples, the eight-hour fasting period and the chemistry-panel statement follow MedlinePlus.
  • The MedlinePlus glucose page does not state units or reference intervals. Use the unit and interval printed on your own report.

General education only. Bring your report, symptoms, and medication list to a qualified healthcare professional for advice about your care. Follow instructions from your lab or clinician if a result is marked critical.