Bloodwork Guide

Comprehensive Metabolic Panel Explained

What the 14 markers in a comprehensive metabolic panel cover and why this panel is a standard safety check before and during a peptide protocol.

Last reviewed September 28, 2026 7 min read By Dave Belmonte, Founder
CMP Safety Baseline Bloodwork
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What's In a Comprehensive Metabolic Panel

A comprehensive metabolic panel, usually shortened to CMP, is one of the most commonly ordered blood tests, in part because it's efficient. A single blood draw returns 14 separate markers covering four different functional systems in the body. It's often the first thing a doctor orders during a routine physical, and it shows up just as often as part of the baseline safety panel for anyone about to start a peptide or NAD+ protocol, alongside the broader set of markers covered in the peptide bloodwork guide.

The 14 markers break into four groups: electrolytes (sodium, potassium, chloride, and carbon dioxide, also reported as bicarbonate), kidney function (BUN and creatinine), liver function (ALT, AST, alkaline phosphatase, and total bilirubin), and blood sugar plus protein status (glucose, total protein, albumin, and calcium). Each group points to a different organ system, so a single marker sitting outside range usually flags one specific area rather than a general problem.

The Four Groups, One at a Time

The table below breaks down what each group is actually checking for, rather than treating the panel as one undifferentiated block of numbers.

Group Markers What It Reflects
ElectrolytesSodium, Potassium, Chloride, CO2Fluid balance and nerve and muscle function
Kidney FunctionBUN, CreatinineHow well the kidneys are filtering and clearing waste
Liver FunctionALT, AST, Alkaline Phosphatase, BilirubinLiver cell health and how the liver is processing what's metabolized
Sugar and ProteinGlucose, Total Protein, Albumin, CalciumBaseline blood sugar and overall protein and nutritional status

What a CMP is not. A CMP is a general organ-function safety check, not a marker of whether a specific compound is working. It tells you the liver and kidneys are handling things normally. Whether a peptide is doing what it's meant to do is a question for markers tied to that compound specifically, such as IGF-1 for a growth-hormone secretagogue.

Why It's a Standard Safety Baseline for Any Peptide Protocol

The liver and kidneys are what process and clear most compounds from the body, peptides included. Confirming both are functioning normally before starting, and checking in periodically during, a longer protocol is standard practice regardless of which specific peptide is being used. It's part of dosing safely, covered in more depth in the peptide dosing guide, rather than something specific to any one compound category.

A CMP is commonly ordered alongside a CBC, since the two panels together cover most of the general safety ground, organ function from the CMP and blood cell counts from the CBC, before layering in whichever compound-specific markers apply to the protocol.

When to Retest

A CMP is commonly retested at the same 8 to 12 week cadence used for other core protocol markers, rather than more frequently. If a new compound is being introduced that carries a notable liver or kidney consideration, it's reasonable to retest sooner, but for most ongoing protocols the standard cycle-length cadence is enough to catch a meaningful shift without chasing normal day-to-day variation.

Once a result is in hand, BioStackIQ's Analyze My Labs tool can read the uploaded report, flag anything outside range, and explain what each marker means in the context of the current protocol.

Frequently Asked Questions

Disclaimer: This content is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before ordering or interpreting lab work, and before starting any peptide protocol.