Unit Conversion for 1.5 mg/dL
To convert 1.5 mg/dL to other concentration units: multiply by 10 to get mg/L (= 15 mg/L), which equals µg/mL (= 1.5 µg/mL); for mmol/L conversion, you must know the molecular weight of the specific substance being measured.
Standard Concentration Conversions
Mass-Based Conversions (Direct)
mg/dL to mg/L: Multiply by 10
- 1.5 mg/dL = 15 mg/L
mg/dL to µg/mL: These are equivalent units (1 mg/dL = 1 µg/mL)
- 1.5 mg/dL = 1.5 µg/mL
Molar Conversions (Substance-Specific)
For mmol/L conversion, you must identify the substance because the conversion requires the molecular weight. The formula is:
- mmol/L = (mg/dL × 10) / molecular weight
Common Examples:
Glucose: Divide mg/dL by 18 (or multiply by 0.0555) 1
- 1.5 mg/dL glucose = 0.083 mmol/L
Lipids: Use substance-specific conversion factors 2
- Triglycerides: Divide by 88.5
- Cholesterol: Divide by 38.7
Important Clinical Context
When to Use Mass vs. Molar Units
Mass units (mg/L, µg/L) are recommended for therapeutic drug monitoring in Australia and New Zealand 3. However, key exceptions exist:
Use molar units for: Lithium (mmol/L), methotrexate (µmol/L), and endogenous substances like minerals, vitamins, and hormones 3
Laboratory reporting standards: Professional guidelines specify that glucose meters should report in plasma glucose concentrations, with the conversion factor clearly stated 1
Critical Pitfall to Avoid
Never convert between mass and molar units for substances like Lp(a) where conversion factors are isoform-dependent and clinically misleading 2. The Canadian lipid guidelines explicitly state that Lp(a) concentrations should not be converted from nmol/L to mg/dL or vice versa.
Practical Application
For clinical use, always verify:
- The specific substance being measured
- Whether your laboratory reports in mass or molar units
- The molecular weight if molar conversion is needed
- Whether the substance has standardized reporting requirements that prohibit conversion