Test Overview

A chemistry screen is a blood test that measures the levels of several substances in the blood (such as electrolytes). A chemistry screen tells your doctor about your general health, helps look for certain problems, and finds out whether treatment for a specific problem is working.

Some chemistry screens look at more substances in the blood than others do. The most complete form of a chemistry screen (called a chem-20, SMA-20, or SMAC-20) looks at 20 different things in the blood. Other types of chemistry screens (such as an SMA-6, SMA-7, or SMA-12) look at fewer. The type of chemistry screen you have done depends on what information your doctor is looking for.

For more information about specific parts of a chemistry screen, see:

• Albumin.
• Alkaline Phosphatase.
• Alanine Aminotransferase (ALT).
• Aspartate Aminotransferase (AST).
• Bilirubin (total and direct).
• Blood Glucose.
• Blood Urea Nitrogen.
• Calcium (Ca) in Blood.
• Carbon Dioxide.
• Chloride (Cl).
• Cholesterol and Triglycerides Tests.
• Creatinine and Creatinine Clearance.
• Gamma-glutamyl transferase (GGT).
• Lactate dehydrogenase.
• Phosphate in Blood.
• Potassium (K) in Blood.
• Sodium (Na) in Blood.
• Total Serum Protein.
• Uric Acid in Blood.