Chem-23 Blood Test: Preparation, Procedure, Results & Risks

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The chem-23 blood test is used to provide doctors with an overview of the patient’s general health. This test may be done as part of a patient’s physical exam or for other reasons based on their doctor’s need to assess their health. Learning more about this test can help a patient better understand its purpose and the results.

Why is It Performed?

This blood test may be ordered for any number of reasons. The most common reasons for having this blood test done include:

  • During a routine physical exam
  • To look for the underlying cause of a specific symptom the patient is experiencing
  • Before having surgery
  • To help plan lifestyle changes or meal plan changes
  • To follow how effective a treatment is going for a specific medical condition

Preparation and Procedure

Preparation will depend on the reason this test is being performed. While fasting is not always required, patients may have to refrain from eating or drinking for nine to 12 hours prior to the test. Water may be permitted, however, if the doctor says the patient can have it.

In most cases, the patient can continue taking his or her medications, though, some medications may need to be stopped or adjusted before the test per doctor’s orders.

Before having this test, usually for at least one to two days prior, patients must not consume alcohol or high-fat foods.

This is a simple blood test in which a blood sample is obtained via using a needle and inserting it into a vein. The technician will allow enough blood to collect, will remove the needle, and the test is complete.

Most patients do perfectly fine for this test, but a small percentage have reported feeling pain during and after they have their blood drawn.

Does Anything Affect the Results?

There are some factors that can affect the results of this test. Any patient with these factors must tell their doctor prior to giving their blood sample. These factors include:

  • Certain medications
  • Consuming alcohol or high-fat foods
  • Vomiting
  • Dehydration
  • Diarrhea
  • Recently having received intravenous fluids


The results for this test are not as simple as they are for other blood tests because multiple things are being tested. Approximate normal results include:

  • Albumin: 3.9 to 5.0 g/dL
  • ALT: 8 to 37 IU/L
  • Alkaline phosphatase: 44 to 147 IU/L
  • AST: 10 to 34 IU/L
  • Calcium – serum: 8.5 to 10.9 mg/dL
  • BUN: 7 to 20 mg/dL
  • Serum chloride: 101 to 111 mmol/L
  • Creatinine: 0.8 to 1.4 mg/dL
  • CO2: 20 to 29 mmol/L
  • Direct bilirubin: 0.0 to 0.3 mg/dL
  • Glucose test: 100 mg/dL
  • Gamma-GT: 0 to 51 IU/L
  • LDH: 105 to 333 IU/L
  • Potassium test: 3.7 to 5.2 mEq/L
  • Phosphorus – serum: 2.4 to 4.1 mg/dL
  • Serum sodium: 136 to 144 mEq/L
  • Total cholesterol: 100 to 240 mg/dL
  • Uric acid: 4.1 to 8.8 mg/dL
  • Total bilirubin: 0.2 to 1.9 mg/dL
  • Total protein: 6.3 to 7.9 g/dL

Abnormal results may indicate a large variety of things. They may indicate diseases and conditions, such as breathing problems, kidney failure, and diabetes-related complications. The patient’s doctor will discuss all results with them and perform any additional testing that may be necessary.


The chem-23 blood test is a basic blood test so there is little risk involved. Though not common, possible risks include:

  • Fainting and lightheadedness
  • Infection
  • Excessive bleeding
  • Hematoma


Horn, T. (2004). Blood Chemistry Tests. Retrieved on January 11, 2011 from the AIDS Community Research Initiative of America:

MedlinePlus. (2010). Comprehensive Metabolic Panel. Retrieved on January 11, 2011 from MedlinePlus: