Unit Converter
Pantothenic Acid (Vitamin B5)
Synonyms
- Pantothenic acid
- Vitamin B5
- Pantothenate
- Calcium pantothenate (supplement form)
- Panthenol (provitamin B5)
- Coenzyme A precursor
Units of Measurement
- µmol/L
- mg/L
- mg/dL
- mg/100 mL
- mg%
- µg/mL
Molecular Weight
219.24 g/mol
Key Unit Conversions
Mass ↔ Molar
1 µmol/L=0.219 mg/L1\ \text{µmol/L} = 0.219\ \text{mg/L}1 µmol/L=0.219 mg/L 1 mg/L=4.56 µmol/L1\ \text{mg/L} = 4.56\ \text{µmol/L}1 mg/L=4.56 µmol/L
mg/dL ↔ mg/L
1 mg/dL=10 mg/L1\ \text{mg/dL} = 10\ \text{mg/L}1 mg/dL=10 mg/L
µg/mL
1 µg/mL=1 mg/L1\ \text{µg/mL} = 1\ \text{mg/L}1 µg/mL=1 mg/L
mg%
\text{mg%} = \text{mg/dL}
Description
Pantothenic acid is an essential water-soluble B-vitamin, required for synthesis of:
- Coenzyme A (CoA)
- Acyl carrier protein (ACP)
These molecules are essential for:
- Fatty-acid oxidation
- TCA cycle (energy production)
- Cholesterol synthesis
- Steroid hormone synthesis
- Neurotransmitter synthesis
- Hemoglobin production
- Detoxification reactions
Vitamin B5 is widely available in foods; deficiency is exceedingly rare.
Most circulating vitamin B5 exists as:
- Pantothenic acid
- 4′-phosphopantetheine
- CoA degradation products
Testing is performed mainly in suspected malnutrition, malabsorption, or inborn errors of metabolism.
Physiological Role
1. Energy Production
Pantothenate → CoA → Krebs cycle & β-oxidation.
2. Fatty Acid Synthesis & Breakdown
Central to lipid metabolism and mitochondrial function.
3. Steroid Hormone Production
Required for adrenal hormones: cortisol, aldosterone.
4. Neurotransmitter Synthesis
CoA needed for acetylcholine synthesis.
5. Hemoglobin Synthesis
Participates in porphyrin pathway.
6. Wound Healing
Pantothenic acid supports epithelial regeneration.
Clinical Significance
HIGH Pantothenic Acid
Usually not clinically significant - often reflects:
- Dietary supplementation
- Energy drinks
- Multivitamin intake
- Parenteral nutrition
- Mild increases in pregnancy or stress states
Vitamin B5 toxicity is rare, as excess is excreted in urine.
LOW Pantothenic Acid (Deficiency)
Rare but clinically relevant.
Causes
- Severe malnutrition
- Alcoholism
- Malabsorption (celiac disease, IBD)
- Prolonged fasting or starvation
- Chronic diarrhea
- Extremely restrictive diets
- Inborn errors affecting CoA metabolism
- Long-term hemodialysis
- Untreated diabetes (excess urinary excretion)
Symptoms
Often nonspecific (“burning feet syndrome”):
- Fatigue
- Irritability
- Numbness/paresthesia
- Muscle cramps
- Sleep disturbances
- Gastrointestinal discomfort
- Hypoglycemia
- Increased insulin sensitivity
Severe deficiency may impair:
- Lipid metabolism
- Adrenal function
- Neuromuscular stability
Reference Intervals
Plasma Pantothenic Acid
- 1.0 – 10.0 µg/mL
(= 1 – 10 mg/L)
(= 4.6 – 45.6 µmol/L)
Deficiency Threshold
- < 1.0 µg/mL (<1 mg/L)
- < 4.6 µmol/L
Urinary Excretion (24 hr)
- Normal: 2–7 mg/day
- Deficiency: < 2 mg/day
Diagnostic Uses
1. Evaluate Malnutrition / Malabsorption
Especially in:
- Celiac
- Crohn’s
- Alcoholism
- Eating disorders
2. Inborn Errors of Metabolism
CoA-related genetic disorders show low pantothenate.
3. Neurologic Disorders
Consider in:
- Burning feet syndrome
- Peripheral neuropathy
4. TPN Monitoring
Pantothenic acid included in parenteral formulations.
5. Research Studies
Energy metabolism, CoA synthesis defects.
Analytical Notes
- Sample: plasma or serum
- Preferred: fasting sample
- Very stable during storage
- LC–MS/MS is gold standard
- Hemolysis does not significantly affect levels
- Check urine if serum levels inconclusive
Clinical Pearls
- True B5 deficiency is rare due to widespread availability in foods.
- Symptoms of deficiency are nonspecific - lab confirmation is essential.
- Multivitamin supplements often contain 5–10 mg/day, well above requirement.
- Plasma levels rise rapidly after supplementation and normalize within hours.
- Pantothenic acid is essential for CoA synthesis, making it central to metabolism.
Interesting Fact
The name “pantothenic” comes from the Greek “pantothen”, meaning “from everywhere”, because vitamin B5 is found in almost every food source.
References
- Tietz Clinical Chemistry & Molecular Diagnostics, 8th Edition - Water-Soluble Vitamins
- NIH Office of Dietary Supplements - Vitamin B5 Fact Sheet
- Mayo Clinic Laboratories - Pantothenic Acid
- ARUP Consult - Vitamin Testing
- EFSA Scientific Panel - B-vitamin Requirements
- MedlinePlus / NIH - Pantothenic Acid Test