LabPreparation

Hormone

IGF-1 Insulin Blood Test Blood Test Preparation: Fasting, Timing

  • Blood draw
  • Hormone
  • Prep checklist included

At a glance

IGF-1 Insulin Blood Test Blood Test: prep snapshot

Sample type
Blood draw
Fasting
Fasting may not be required for a routine IGF-1 order, but requirements can vary by lab…
Best collection time
IGF-1 levels are fairly stable, so the sample can usually be collected at any convenient time.
Typical turnaround
Varies by collection lab
Category
Hormone

This page explains how to prepare for a IGF-1 Insulin Blood Test, what the test measures, and what to confirm with the collection lab. The IGF-1 Insulin Blood Test measures insulin-like growth factor 1, a hormone that reflects growth hormone activity in the body.

What the IGF-1 Insulin Blood Test measures

It measures the amount of IGF-1 circulating in the bloodstream. IGF-1 is produced largely in response to growth hormone, so the result reflects growth hormone activity over time. The test reports a single IGF-1 value rather than a panel of multiple analytes.

Getting ready for the IGF-1 Insulin Blood Test

Routine orders rarely require special preparation. The testing location can confirm any timing or fasting details when you book.

  1. Confirm with the collection lab whether fasting is needed for your specific order.
  2. Ask the lab whether a particular time of day is preferred for the draw.
  3. Bring a list of medications and supplements you currently take.
  4. Wear a short-sleeved or loose-fitting top for easy arm access.
  5. Drink water beforehand unless the lab tells you otherwise.
  6. Arrive with your test order or requisition if one was provided.

Fasting, timing, sample type, and what to bring

Fasting

Fasting may not be required for a routine IGF-1 order, but requirements can vary by lab and by the reason for testing; confirm with your lab.

Best time to collect

IGF-1 levels are fairly stable, so the sample can usually be collected at any convenient time. If your clinician or lab specifies a preferred time, follow that instruction.

Sample type

Blood draw. The collector will explain the process before starting.

What to bring

  • Your order confirmation email, in case the collection site asks to see it
  • Your printed lab order or requisition form — the ordering physician prepares it for you after you order, and you print it (or fax it from your account) before visiting
  • Water to drink before the draw and a light snack for afterward, if your test requires fasting
  • A government-issued photo ID (most collection sites verify identity at check-in)
  • A written list of the medications and supplements you currently take
  • A short-sleeved or loose-sleeved shirt for an easy blood draw

You do not need an insurance card or a payment method at the collection site: the lab does not bill insurance, and you pay at order time, so there is no copay or deductible. The lab also provides the physician's requisition, so you do not need a separate doctor's referral.

Order process and what-to-bring details reflect the lab's published instructions, paraphrased in our own words. Confirm final requirements with the collection lab that will perform your draw.

The collection visit, step by step

A phlebotomist cleans an area on your arm and inserts a small needle into a vein to collect a blood sample. The draw usually takes only a few minutes, and the sample is then sent to the laboratory for analysis.

Details worth confirming with the collection lab before your visit:

  • Do I need to fast before this test?
  • Is there a preferred time of day for the blood draw?
  • When can I expect my results?

Why a clinician may order this test

A clinician may order this test to evaluate growth hormone activity when growth or hormone-related concerns are present. It can also be used to monitor conditions or treatments that affect growth hormone levels.

What results mean

Reference ranges for IGF-1 vary by laboratory and are often age-dependent, so results should be interpreted using the range provided by the testing lab. Your clinician can explain what your specific value means in the context of your health.

General test information is compiled from publicly available reference material, including MedlinePlus (medlineplus.gov) and the Centers for Disease Control and Prevention (cdc.gov), and is reviewed for clarity. Preparation and what-to-bring details reflect the lab's published instructions, paraphrased into our own words. Preparation instructions, timing, and pricing vary by collection lab — always confirm them with the lab that will perform your draw.

Common questions

Frequently asked questions

Do I need to fast for the IGF-1 Insulin Blood Test?

Fasting is often not required for a routine IGF-1 order, but requirements can differ by lab and by the reason for testing. Confirm with your collection lab before your appointment.

How long does it take to get results?

Turnaround is typically one to three business days after the sample reaches the laboratory. Your ordering clinician or the lab can give you the specific timeline.

Is this test the same as a growth hormone test?

No, it measures IGF-1, which is a hormone produced in response to growth hormone. Because IGF-1 levels are steadier, it is often used as an indicator of growth hormone activity over time.

Can I take my medications before this test?

In most cases you can take your usual medications, but some medicines can affect IGF-1 levels. Tell the lab and your clinician about everything you take so they can advise you.