Labs

The baseline blood panel: what to test before any peptide protocol

Creator: Halftime Health
Published: 2026-04-29
Keywords: baseline blood panel before peptides, blood work before peptides, labs before peptide therapy, peptide therapy lab work, peptide protocol baseline

7 min read · Updated 2026-10-09

The short version: you cannot measure progress without a starting number.

TL;DR

A baseline blood panel anchors a peptide protocol in numbers, not impressions.
Core panel: CMP, lipid panel, A1C, fasting insulin, IGF-1, sex hormones, hs-CRP.
Most panels need a fasting, early-morning draw.
Retest the relevant subset at 8 to 12 weeks to see what changed.

What it is

A baseline blood panel is the set of lab tests drawn before a peptide protocol begins. It captures where your body is right now so any change can be measured against it later. It also does a second job that gets less attention: it screens for problems that make a protocol a bad idea in the first place. The standard panel is built from broadly available, well-validated tests. Most are commonly run by primary care.

How it works

Think of it like weighing your luggage before a trip. The number itself is not the point. The point is being able to say at the end of the trip whether anything was added or removed. Each test in the panel measures one specific system.

Blood work before peptides, grouped in plain words

Organ function and blood counts

CMP (comprehensive metabolic panel). Fourteen measurements covering kidney function, liver function, electrolytes, blood sugar, and proteins (MedlinePlus, CMP, 2024). Think of it as the safety floor for everything else.
CBC (complete blood count). Red cells, white cells, and platelets.

Heart and lipids

Lipid panel. LDL, HDL, triglycerides, and total cholesterol (CDC, Getting Your Cholesterol Checked). Some physicians add ApoB, which reflects the number of cholesterol-carrying particles (American Heart Association, 2026).

Blood sugar and metabolism

A1C. Your average blood sugar over the past 2 to 3 months. The CDC lists below 5.7% as normal and 5.7% to 6.4% as prediabetes (CDC, Diabetes Testing). Anemia and kidney or liver disease can make A1C less accurate (MedlinePlus, A1C test), which is one more reason to run it alongside a CBC and CMP.
Fasting insulin. It can show insulin resistance years before A1C moves.

Hormones

IGF-1. The downstream signal of the growth hormone axis.
Sex hormones. Total and free testosterone for men. Estradiol and progesterone for women. Testosterone is usually drawn between 7 and 10 a.m., when levels are typically highest (MedlinePlus, Testosterone levels test).

Inflammation

hs-CRP. Shows how much inflammation is in your body, but not what is causing it or where. Infections raise it (MedlinePlus, CRP test), so a baseline drawn while you are sick can mislead.

Why a baseline matters: two jobs

Job one is safety. A kidney, liver, blood count, or blood sugar problem changes what is appropriate, or whether anything should be prescribed at all. Finding it before a protocol starts is the whole point.

Job two is comparison. If you retest at 8 to 12 weeks and something moved, you can see it. Without the first number, you are guessing. For the second number to mean anything, test the same way each time: same prep, same time of day, and ideally the same lab. Labs use different methods and reference ranges, and MedlinePlus advises using the same lab when tracking results over time (MedlinePlus, How to understand your lab results).

Getting tested: fasting, timing, and where

Fasting. Glucose and lipid tests usually need an 8 to 12 hour fast. Plain water is fine. Skip coffee, juice, gum, and exercise during the fast (MedlinePlus, Fasting for a blood test).
Morning draw if hormones are on the panel.
Medicines and supplements. Tell your provider about everything you take. Don't stop any medicine unless your provider tells you to.
No hard workout first. Hard exercise before a test can affect some results (MedlinePlus, How to understand your lab results).
At home or at a lab. Many baseline markers can be collected at home and processed by a certified lab. Here is what makes an at-home blood test accurate.

What results can and cannot tell you

Reference ranges come from large groups of healthy people, and it is common for a healthy person to land outside one now and then (MedlinePlus). A single result is a snapshot. Your baseline cannot tell you whether a peptide is right for you. That decision belongs to a physician who weighs your labs, history, goals, and medicines together. And a "normal" panel is not a green light on its own, just as one flagged number is not a red light on its own.

Questions to ask any provider before you pay

Are labs required before any prescription?
Which tests are included, listed by name?
Who reviews my results, and is that physician licensed where I live?
What happens if my labs don't support a protocol?
When do I retest, and is the retest included?
Will I see my actual numbers and reference ranges?

For the full process from intake to pharmacy, see what online peptide therapy actually looks like.

Who asks about it

People ask this when their physician requests labs and they want to know which tests are core, which are optional, and why each one is on the list.

What the research says

The CMP and lipid panel are foundational because they are the most extensively validated reference tests in adult medicine. A1C reflects average blood glucose over roughly the prior 2 to 3 months and is a standard diagnostic test for type 2 diabetes. Fasting insulin is included because it can detect insulin resistance years before A1C moves out of normal range. IGF-1 is included for any growth-hormone-axis peptide because it is the downstream signal those peptides ultimately influence.

What to know before considering it

A baseline panel is not a substitute for a physician evaluation. It is an input to one. Lab values vary by lab and reference range, and some peptide-relevant markers (fasting insulin, hs-CRP, IGF-1) are not always part of a generic primary-care panel. If you are not sure whether you need a full panel at all, start with who should get a comprehensive biomarker panel and when.

The Halftime POV

If your clinic is willing to start a protocol without baseline labs, that is a signal. Quality care starts with numbers.

How Halftime does this

Halftime Health membership includes an onboarding blood panel you collect at home. A licensed physician reviews your labs and decides whether a protocol is appropriate for you. If a protocol is prescribed, a licensed 503A compounding pharmacy fills it. You retest later to see what changed. Read more about how Halftime blood testing works.

Related reading:

FAQ

Q: What labs should I get before starting peptide therapy? A: A typical baseline panel includes a comprehensive metabolic panel, lipid panel, A1C, fasting insulin, IGF-1, total and free testosterone (men) or estradiol and progesterone (women), and hs-CRP. Your physician will tailor the list to your goals and history.

Q: Why do I need a baseline panel? A: Without a starting number, you cannot tell whether a protocol is doing anything. Baseline labs give you a comparison point at 8 to 12 weeks and flag safety issues that can change the decision to prescribe at all.

Q: Do I need to fast before blood work for peptides? A: Usually, yes, if the panel includes glucose or a lipid panel. Those typically need an 8 to 12 hour fast with only plain water. Hormone tests such as testosterone are best drawn early in the morning. Follow the instructions you are given, and don't stop any medicine unless told to.

Q: Can I use labs from my own physician? A: Often, if they are recent and cover the markers needed. Most physicians prefer labs drawn within the last 60 to 90 days, because older labs do not reflect current physiology and are not a fair comparison after a protocol begins.

Disclaimer

This article is educational and is not medical advice. Compounded medications are not FDA-approved. Clinical outcomes depend on individual factors and require physician evaluation. Results vary.

Get started

We share what we learn along the way: the research, the regulations, the real-world trade-offs. Get started with Halftime Health.

Sources

Frequently asked questions

What labs should I get before starting peptide therapy?

A typical baseline panel includes a comprehensive metabolic panel, lipid panel, A1C, fasting insulin, IGF-1, total and free testosterone (men) or estradiol and progesterone (women), and hs-CRP. Your physician will tailor the list to your goals and history.

Why do I need a baseline panel?

Without a starting number, you cannot tell whether a protocol is doing anything. Baseline labs give you a comparison point at 8 to 12 weeks and flag safety issues that can change the decision to prescribe at all.

Do I need to fast before blood work for peptides?

Usually, yes, if the panel includes glucose or a lipid panel. Those typically need an 8 to 12 hour fast with only plain water. Hormone tests such as testosterone are best drawn early in the morning. Follow the instructions you are given, and don't stop any medicine unless told to.

Can I use labs from my own physician?

Often, if they are recent and cover the markers needed. Most physicians prefer labs drawn within the last 60 to 90 days, because older labs do not reflect current physiology and are not a fair comparison after a protocol begins.

Membership includes a blood panel you collect at home. A licensed physician reviews your labs.

Membership from $39/mo, or $390 for the year, including your onboarding panel. Each protocol is its own monthly subscription.

Join Now →See the blood panel

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