The Ultimate Guide to NCLEX Lab Values: Reference Ranges You Must Know

Essential NCLEX Lab Values

Knowing normal lab value ranges is critical for NCLEX success. Here's a comprehensive guide to the values you must memorize.

Complete Blood Count (CBC)

• WBC: 5,000-10,000/mm³
• RBC: 4.5-6.0 million/mm³ (male), 4.0-5.5 million/mm³ (female)
• Hemoglobin: 14-18 g/dL (male), 12-16 g/dL (female)
• Hematocrit: 42-52% (male), 37-47% (female)
• Platelets: 150,000-400,000/mm³

Electrolytes

• Sodium: 135-145 mEq/L
• Potassium: 3.5-5.0 mEq/L
• Calcium: 9.0-10.5 mg/dL
• Magnesium: 1.5-2.5 mEq/L
• Phosphorus: 3.0-4.5 mg/dL
• Chloride: 98-106 mEq/L

Coagulation Studies

• PT: 11-12.5 seconds
• INR: 0.8-1.2 (therapeutic 2.0-3.0 for warfarin)
• aPTT: 30-40 seconds (therapeutic 1.5-2.5 times normal for heparin)

Cardiac Markers

• Troponin I: <0.04 ng/mL
• CK-MB: 0-3% of total CK
• BNP: <100 pg/mL

Renal Function

• BUN: 7-20 mg/dL
• Creatinine: 0.6-1.2 mg/dL
• eGFR: >60 mL/min/1.73m²

Liver Function

• ALT: 7-56 U/L
• AST: 10-40 U/L
• Bilirubin: 0.1-1.2 mg/dL
• Albumin: 3.5-5.0 g/dL

Endocrine

• Fasting glucose: 70-100 mg/dL
• HbA1c: 4.0-5.6% (normal), 5.7-6.4% (prediabetes), ≥6.5% (diabetes)
• TSH: 0.4-4.0 mIU/L
• Free T4: 0.8-1.8 ng/dL

Practice with NCLEX Prep AI's Lab Values Quiz tool to reinforce these ranges and test your knowledge with interactive quizzes.