A blood biochemistry panel — also called a chemistry or metabolic panel — measures enzymes, proteins and waste products in serum to show how your liver and kidneys are working. Read together, its markers separate a liver problem from a kidney one and give a first sense of how severe it is.
What the biochemistry panel measures
The panel covers three overlapping systems. Liver enzymes and bilirubin report on the liver and bile ducts; creatinine and urea report on kidney filtration; and the serum proteins plus uric acid sit across both, reflecting nutrition, inflammation and metabolism. Grouping them works because organ function is a network — the liver makes the proteins the kidneys help conserve, so a single sample builds a joined-up picture. Labs offer a basic version focused on the kidneys and a comprehensive version that adds the full set of liver markers, but the reading logic is the same.
No marker is read in isolation. A raised liver enzyme means little until you see which other enzymes moved with it, and a creatinine is interpreted against age, sex and hydration rather than a fixed cutoff.
Which tests are included
- ALT — a liver-specific enzyme; rises when liver cells are injured.
- AST — an enzyme in liver and muscle; read together with ALT.
- Alkaline phosphatase — from the bile ducts and bone.
- GGT — a bile-duct enzyme; confirms a liver source and flags alcohol.
- Bilirubin — the pigment that causes jaundice when it builds up.
- Total protein — all the proteins in serum combined.
- Albumin — the main serum protein, made by the liver.
- Creatinine — muscle waste filtered by the kidney; the key kidney number.
- Urea — nitrogen waste; reflects kidney function and hydration.
- Uric acid — purine waste; high levels can cause gout.
Creatinine is reported in mg/dL in the US and µmol/L elsewhere; a unit converter turns one into the other so the number reads the same on any report.
When doctors order it
Biochemistry is a standard part of the annual checkup and of any hospital work-up. It is drawn before and during treatment with medicines that can affect the liver or kidneys — statins, some antibiotics, long-term painkillers — and to investigate symptoms such as jaundice, dark urine, abdominal pain, swelling of the legs, or persistent fatigue. It also tracks known liver and kidney disease over time.
How to prepare
For liver and kidney markers alone, fasting is usually not required, though it is often requested because the panel is bundled with a fasting glucose or lipid test — then fast 8 to 12 hours with water allowed. Avoid strenuous exercise beforehand, which can raise AST from muscle, and mention any supplements or medication, since many alter these results.
How to read the results together
- Liver pattern. ALT and AST rising together point to injured liver cells, while alkaline phosphatase and GGT rising together point to a blocked or irritated bile duct. A high GGT confirms that a raised alkaline phosphatase comes from the liver rather than bone.
- Kidney pattern. Creatinine and urea rising together suggest reduced filtration; urea rising alone, with normal creatinine, more often means dehydration or a gut bleed.
- Protein pattern. A low albumin, read with total protein, can reflect chronic liver disease, poor nutrition or protein lost through the kidneys or gut.
- Uric acid. A high uric acid is read largely on its own — it drives gout — but seen next to the kidney markers it also hints at how well the kidneys are clearing it.
When to retest
Mildly raised liver enzymes in someone who feels well are typically rechecked in a few weeks to a few months, often after cutting alcohol or losing weight, before any further tests. Kidney markers in stable chronic disease are monitored on a schedule the doctor sets, and are also checked when a new medication that leans on the liver or kidneys is started. Markedly abnormal results, jaundice, or a sharp change in kidney numbers should be reviewed promptly. Read every value against your own lab’s range and let the ordering doctor decide the next step.
