Continuing Education Activity

Vitamin B5 is a medication used in the management and treatment of nutrient deficiencies. It is in the dietary supplement class of medications. This activity reviews the indications, actions, and contraindications for vitamin B5 as a valuable agent in treating nutritional deficiencies. This activity will highlight the mechanism of action, adverse event profile, and other key factors in the treatment of patients with nutritional deficiencies and related conditions.

Objectives:

• Describe the indications for vitamin B5 usage.
• Review the mechanism of action for vitamin B5.
• Explain the methods of drug administration.
• Identify risks associated with overdose of vitamin B5.

Indications

Vitamin B5 (pantothenic acid) supplements are not subject to initial review by the U.S. Food and Drug Administration (FDA). The agency does not have the authority to examine dietary supplement products for safety and effectiveness prior to marketing. Out of all the drugs listed in this indications section, only panthenol and dexpanthenol are approved by the FDA for use in cosmetics. All other indications listed are non-FDA approved.

Vitamin B5 is a naturally occurring substance found in various plants and animals (i.e., eggs, milk, vegetables, beef, chicken, and whole grains). It is also artificially added to foods. B5 deficiency is generally rare since the vitamin is present in many foods. However, it can present in people with severe malnutrition. An individual with vitamin B5 deficiency commonly has deficiencies in other nutrients, which can make it challenging to identify the effects that are specific to vitamin B5 deficiency. An experimental vitamin B5 deficiency study associated the deficiency with symptoms such as fatigue, headache, malaise, personality changes, numbness, muscle cramps, paresthesia, muscle/ abdominal cramps, nausea, and impaired muscle coordination.[1]

Individuals with a mutation in their pantothenate kinase 2 (PANK2) gene are likely to have a pantothenic acid inadequacy as well. Enough PANK2 mutations reduce the activity of pantothenate kinase 2, which can potentially decrease the conversion of pantothenic acid to coenzyme A (CoA) and lead to reduced CoA levels. PANK2 gene mutations also cause pantothenate kinase-associated neurodegeneration (PKAN). A common hallmark of individuals with PKAN is an accumulation of iron in the brain that forms a pattern called the "eye of the tiger" sign.[2] This disease also presents with a progressive movement disorder, and other symptoms may vary significantly from case to case. Symptoms include dysarthria, dystonia, poor balance, spasticity, and muscle rigidity. Treatment of this condition focuses mainly on reducing symptoms. A few anecdotal reports indicate that vitamin B5 supplements can reduce symptoms, but the benefits of the general use of this supplement in PKAN are not known.[3]

The usage of vitamin B5 is prevalent within the field of dermatology. There is a growing interest in the various effects of nonsteroidal anti-inflammatory drugs (NSAIDs).[4] This interest has led to a study that compares the effectiveness of dexpanthenol (an alcoholic analog of D-pantothenic acid) as an alternative treatment to atopic dermatitis against a standard treatment of hydrocortisone. Overall, the study found that dexpanthenol can potentially treat mild to moderate childhood atopic dermatitis therapy.[5] Other research suggests that dexpanthenol cream can be useful in managing mucocutaneous side effects that occur during isotretinoin therapy.[6] Isotretinoin therapy is used as a treatment for acne, and its mucocutaneous side effects include dryness of mucous membranes, cheilitis, and xerosis. 

Clinical studies have shown the evaluation of dexpanthenol in wound healing applications. These small clinical trials used the drug as a pastille and or spray to heal wounds in postoperative endotracheal intubation, endoscopic sinus surgery, and tonsillectomy.[7][8][9] The use of dexpanthenol shows better clinical outcomes in these clinical trials. Regardless, further studies are necessary to generalize drug efficacy. 

Dyslipidemia is another field that can potentially use vitamin B5. Since vitamin B5 is essential for the biosynthesis of coenzyme A, it plays a role in the metabolism of lipids. One study concluded that pantethine (a derivate of vitamin B5) lowered cardiovascular disease risk markers in low to moderate-risk participants.[10] These risk markers include LDL, HDL, and total cholesterol. 

Pantothenate deficiency can play a vital role in Ach deficiency, neurodegeneration, myelin loss, and age-related dementias like Huntington disease.[11] Nevertheless, more studies are still needed to test the clinical efficacy of vitamin B5 in these conditions.

Mechanism of Action

Vitamin B5 is exclusively a precursor in the synthesis of CoA and thus only directly affects this metabolic pathway. CoA has a role in hundreds of human biochemical reactions such as cell growth, intermediary metabolism, and neurotransmitter synthesis.[12][13] The structure of CoA functions as a carbonyl-activating group and as an acyl group carrier to help facilitate these various reactions.[14]

Administration

Dietary supplements of vitamin B5 are available as vitamin B5 exclusively or in combination with other vitamins in multivitamin/multimineral products. Patients normally administer these supplements orally. Depending on the application, derivatives of vitamin B5 can be applied topically and even through injection using IV formulas. Dexpanthenol administration can be via an oral spray applied in the mouth.[9]

Adverse Effects

Vitamin B5 doses are age-dependent, and if the patient is pregnant or lactating. Doses greater than 10mg/day may cause mild diarrhea or mild intestinal distress.[15] There have been cases reported of allergic contact dermatitis with the topical use of panthenol cream and dexpanthenol.[16][17]

Contraindications

The following drugs have moderate interactions with vitamin B5:

• Azithromycin
• Clarithromycin
• Erythromycin base
• Erythromycin ethylsuccinate
• Erythromycin lactobionate
• Erythromycin stearate
• Roxithromycin

Furthermore, there are at least 60 other drugs that have mild interactions with vitamin B5. Other contraindications include patients with hypersensitivity or allergy to the drug or any of its derivatives. A report suggests that vitamin B5 intake might correlate with increased cerebral amyloid-beta peptide burden in individuals with cognitive impairment.[18] Although further studies are still needed to confirm the findings and discover the molecular mechanisms of this pathway, the current research suggests those with cognitive impairment to be a potential contraindication.[18]

Monitoring

Vitamin B5 is considered relatively safe. Dosages above the recommended amount can induce mild diarrhea/ intestinal distress. Allergic reactions and hypersensitivity can occur with the derivatives of vitamin B5 as well.

Recommended Daily Intake[19][20][21][22][23]

• Take with food if administered orally
• Men and Women over 19 years and older: 5 mg/day
• Pregnant women: 6 mg/day
• Lactating women: 7 mg/day
• Children under 6 months: 1.7 mg/day
• Children 7 to 12 months: 1.8 mg/day
• Children 1 to 3 years: 2 mg/day
• Children 4 to 8 years: 3 mg/day
• Children 9 to 13 years: 4 mg/day
• Children 14 to 18 years: 5 mg/day

Toxicity

As previously stated, vitamin B5 is considered generally safe.[15] There are currently no upper limits established since there have been no reports of vitamin B5 toxicity in humans with high intakes. However, there are still side effects involved with the administration of this drug, which includes the following (these lists are not all-inclusive):

Common Side Effects

• Muscle pain
• Joint pain
• Diabetes mellitus, new-onset
• Sore throat
• Headache
• Weakness/lack of energy
• Dizziness 
• Creatine phosphokinase (CPK) increased
• Nausea 
• Abdominal pain
• Alanine transaminase (ALT) increased
• Constipation 
• Flulike illness
• Urinary tract infection (UTI) 
• Hypersensitivity reactions (including rash, itching, hives, and swelling)
• Pancreatitis

Less Common Side Effects

• Yellowing skin and eyes (jaundice)
• Muscle disease
• Muscle wasting (rhabdomyolysis)

Enhancing Healthcare Team Outcomes

Vitamin B5 levels are obtainable through either blood or urine tests. The proper evaluation and classification of nutrient deficiencies lead to improved patient healthcare outcomes. Cohesiveness and open communication among the members of a patient’s interprofessional healthcare team allow for optimal therapy and necessary interventions. This team will include clinicians, nurses, pharmacists, and dieticians, all engaged in open communication and working collaboratively to achieve optimal patient outcomes. [Level 5]