Vitamin B3

Biochemical action of Vitamin B3

Vitamin B3 belonging to the water-soluble vitamin is vital for maintaining overall health.

Two coenzymes, coenzyme 1 is the oxidised form of nicotinamide adenine dinucleotide [NAD]) and coenzyme 2 is the reduced form of nicotinamide adenine dinucleotide phosphate [NADP]), which either accept or donate hydrogen ions in necessary oxidation-reduction reactions, are vital for adequate cellular metabolism and function. These two coenzymes are essential for lipid metabolism, tissue respiration, glycogenolysis, and the suppression of the formation of very low-density lipoprotein (VLDL). It accelerates the elimination of plasma chylomicron triglycerides.

Vitamin B3 is available in the form of tablets and capsules.

Tablets/ capsules are to be swallowed whole with water/liquid, as applicable.

Vitamin B3 can be used as a supplement support for-.

• Lowering of cholesterol: Niacin prescription medicines should be taken orally in the amount of 500 mg or greater to reduce abnormal cholesterol.
• Pellagra: Niacin is indicated in the treatment of pellagra until the symptoms resolve, most commonly to relieve skin symptoms.
• Anti-oxidant: Niacin decreases the risk of cardiovascular disease by exhibiting many pleiotropic effects, especially by its anti-oxidative and anti-inflammatory actions and by increasing serum adiponectin.

Vitamins and natural supplements should not replace a balanced diet

This product is not intended to diagnose, treat or prevent any disease(s).

Vitamin B3 may be useful as a supplement for the following health benefits:

• Dyslipidemia: High-density cholesterol (HDL) may be effectively elevated by niacin, with a rise of 15% to 35%. When administered at a therapeutic dose, Niacin can lower total cholesterol by up to 25%, LDL by up to 10% to 15%, and triglycerides by up to 20% to 50%. The recommended dosage for hyperlipidemia is 1 to 6 grams daily, starting at low doses (100 mg three times daily) and increasing at weekly intervals based on tolerance and effect.

• Osteoarthritis: Vitamin B3 may help alleviate osteoarthritis, based on human studies. It has been shown that vitamin B3 promotes joint flexibility, decreases inflammation, and the overall effects of osteoarthritis.

• Neurological function: Vitamin B3 helps to keep healthy nerve cells and supports the proper functioning of the nervous system.The adequate dietary intake of vitamin B3 is thought to enhance neuronal function and slow neurodegeneration, according to several clinical studies.

• Anti-oxidant: Vitamin B3 possesses antioxidant properties which help scavenge the body from damaging free radicals. Niacin supplement decreases the risk of cardiovascular disease by exhibiting many pleiotropic effects, especially by its anti-oxidative and anti-inflammatory actions and by increasing serum adiponectin.
• Energy Production: The metabolism of carbohydrates, lipids, and proteins depends on vitamin B3, which is necessary for transforming food into energy.
• Skin Health: Niacin supports the formation of skin cells and maintains adequate moisture levels, which helps to maintain healthy skin.
• Regulates Blood Sugar Levels: Vitamin B3 supplement can be beneficial in regulating blood sugar levels while improving overall metabolic health.
• Digestive Health: Vitamin B3 supplement helps to keep the gastrointestinal tract healthy and promotes healthy digestion.

Vitamin B3 is commonly administered orally before or after meals for all oral solid forms.

The dosage and duration of treatment should be as per the clinical judgment of the treating healthcare professional.

Vitamins and natural supplements should not replace a balanced diet

This product is not intended to diagnose, treat or prevent any disease(s).

• Tablet: 50mg,100mg, 250mg, 500mg
• Tablet extended-release: 500mg, 750mg, 1000mg
• Capsule extended-release: 250mg, 500mg

Dosage Adjustment in Adult Patients

Dietary supplement (OTC)

50 mg orally for every 12hr or 100 mg oral every Day; various forms are known.

Hyperlipidemia

Immediate-release: 250 mg orally once daily; dose or frequency adjusted every 4 to 7 days based on effect and tolerance to the first-level therapeutic dose of 1.5 to 2 g orally divided every 6-8hr, then changed every 2 to 4 weeks but recommended not to exceed 6 g/day.

Extended-release: 500 mg/day orally at bedtime initially; dose adjusted every 4 weeks based on effect and tolerance to therapeutic dose of 1to 2 g once daily but not to exceed 1-2 g/day.

Pellagra (Off-label)

50-100 mg orally every 6-8hr but not to exceed 500 mg/day.

Vitamin B3 is available in the form of tablets and capsules.

• Limit the consumption of drinks that include caffeine, such as coffee, tea, chocolate, and alcoholic beverages, as this substance could hinder the absorption of Vitamin B3.
• Avoid the consumption of foods that are high in fat or cholesterol, or niacin will be less effective.
• Stay within your daily calorie needs.
• Avoid spicy foods.

The dietary restriction should be individualized as per patient requirements.

Recommended Daily Allowance (RDA)

The RDA of niacin for adults is 16 mg/day of Niacin Equivalents (NEs) for men and 14 mg/day of NEs for women.

Upper Tolerable Intake (UTL):

UTL for adults is 35 mg/day.

• Peptic ulcer disease
• Active hepatic disease or elevation in transaminases
• Hypersensitivity reactions
• Niacin interferes with blood sugar control during and after surgery.
• Niacin is avoided in patients with a history of gout as it causes hyperuricemia.
• The risk of infections in xanthomas may be raised by taking niacin.
• Severe hypotension, arterial bleeding
• Persistent, unexplained elevation of serum aminotransferase
• Patients having a history of liver illness, gout or gouty diathesis, diabetes mellitus, gallbladder disease, CVD, renal or hepatic impairment should be administered with caution.
• If patients are on HMG-CoA reductase inhibitors or anticoagulants, or if myopathy symptoms develop, treat cautiously (monitor creatine phosphokinase).
• Immediate-release and extended-release dosage forms are not interchangeable.

The treating healthcare professional must closely keep a watch and monitor for signs and symptoms of adverse reactions, such as flushing, itching, and gastrointestinal discomfort.

Individuals having pre-existing medical conditions, such as liver disease, kidney disease, diabetes, or gout, should consult the physician before taking vitamin B3 supplements.

Vitamin B3 supplementation is reported to be well-tolerated and safe to use.

The adverse reactions related to Vitamin B3 can be categorized as-

• Common: Flushing, GI distress, and pruritus
• Less common: Hepatotoxicity
• Rare: Anaphylaxis and death.

• Isoniazid and pyrazinamide: Drugs that are used to treat tuberculosis, such as isoniazid and pyrazinamide, prevent the body from converting tryptophan to niacin. Your body's levels of niacin could decrease due to this interference.
• Antidiabetes medications: People are recommended to have their blood glucose levels checked if they use high-dose nicotinic acid supplements and any anti-diabetic medications since they might require modifying the amount they consume.1,500 mg or more of nicotinic acid per day or higher dosages can adversely affect blood sugar control and the efficiency of diabetic treatments. These dosages may even cause persons without diabetes to have higher blood sugar levels.
• Alcohol: Flushing and itching are side effects of niacin. Niacin may worsen the flushing and itching if alcohol is consumed. Additionally, there is some risk that mixing alcohol and niacin may raise the risk of developing liver damage.
• Allopurinol: Taking large doses of niacin might worsen gout and decrease the effects of allopurinol.
• Statins: Taking niacin and statins might increase the risk of muscle damage in some people. Use with caution.

The common side effects associated with Vitamin B3 include:

• Diarrhea
• Headache
• Stomach discomfort
• Bloating
• Itching
• Flushing characterised by sense of warmth in the face, ears, neck and trunk
• Erythema (skin redness)
• Tingling

• Pregnancy:

The recommended daily intake of Vitamins is 18 mg/day. Excessive consumption of vitamin B3 may harm both the woman and the fetus.

There is no sufficient scientific evidence regarding the use and safety of Vitamin B3 for special populations.

• Paediatrics:

Vitamin B3 deficiency is higher in children, especially babies; it plays a critical role in promoting brain growth, sustaining cell function, and the development and protection of the body's nervous system.

Dosage Adjustment for Paediatric Patients

Nutritional Supplementation

The recommended daily intake of Vitamin B3 ranges from 2-16 mg/day.

Pellagra (Off-label)

50-100 mg PO q8hr

Monitor LFTs

• Geriatrics:

Vitamin B3 is an excellent antioxidant- helping maintain the cells' health and function, thus reducing the risk of age-related diseases, such as heart disease and dementia.

There is no sufficient scientific evidence traceable regarding the use and safety of Vitamin B3 for use in special populations

• Lactating mothers:

Vitamin B3 is a normal component of human milk and is a key milk antioxidant.

The recommended daily intake for lactating mothersis 17 mg/day.

There is no sufficient scientific evidence traceable regarding the use and safety of Vitamin B3 for use in special populations.

Dosage Adjustment in Kidney Impairment

Niacin above 500 mg daily may be accumulated in people with kidney disease.

There are no specific dosage adjustments provided.

Dosage Adjustment in Hepatic Impairment

High niacin dosages might worsen liver damage. If you have liver disease, avoid using high doses.

There are no specific dosage adjustments provided.

Dosage Adjustment in Adult Patients

Dietary supplement (OTC)

50 mg PO q12hr or 100 mg PO qDay; many formulations exist.

Hyperlipidemia

Immediate-release: 250 mg PO once daily; dose or frequency adjusted every 4-7 days based on effect and tolerance to the first-level therapeutic dose of 1.5-2 g PO divided q6-8hr, then changed every 2-4 weeks; not to exceed 6 g/day.

Extended-release: 500 mg/day PO at bedtime initially; dose adjusted every 4 weeks based on effect and tolerance to therapeutic dose of 1-2 g once daily; not to exceed 1-2 g/day.

Pellagra (Off-label)

50-100 mg PO q6-8hr; not to exceed 500 mg/day.

Overdosage of vitamin B3 supplements may show symptoms like flushing, headache, lightheadedness, itching, nausea, and vomiting, which are self-limiting.

There is no specific treatment in the event of an overdose. In the event

of an overdose, the mainstay treatment is stopping the exogenous vitamin B3 supplementation and treating the patient symptomatically, and supportive measures are instituted as required.

Biochemistry profile of Vitamin B3:

Nicotinamide, nicotinic acid, and other related substances comprise niacin, often known as vitamin B3. While nicotinamide has a pyridine ring with a substituted amide group, nicotinic acid has a pyridine ring with a substituted carboxylic acid group.

Niacin serves as a cofactor in dehydrogenase enzymes, facilitating the transfer of hydride ions. This vitamin is essential for the formation of the electron carriers NAD and NADP, which are required for cellular redox processes as acceptors or donors of hydride ions, NAD and NADP promote metabolic activities. These coenzymes also aid dehydrogenases, which are necessary for cellular energy synthesis.

Kinetic profile:

• Absorption: Niacin is a water-soluble vitamin absorbed into the blood from the gastrointestinal tract, specifically from the small intestine, through active transport at nutritional doses and passive diffusion at pharmacologic doses.
• Distribution: Nicotinamide, the predominant circulating form of the vitamin, is transported to tissues to synthesise NAD or NADP.
• Metabolism: The body produces NAD and NADP coenzymes from nicotinamide or nicotinic acid, which alters tissue concentration. NAD levels are affected by hormonal and hepatic regulation of extracellular nicotinamide. Niacinamide is released from NAD hydrolysis in the liver and transported to tissues without the ability to synthesize NAD. The liver converts extra plasma nicotinamide to storage NAD. Tryptophan and nicotinic acid are the niacin biosynthesis pathway components, contributing to maintaining NAD. Nicotinamide is also produced when NAD degrades and is subsequently transformed into NAD by nicotinamide ribonucleotide. Additionally, nicotinamide is deamidated in the digestive tract by intestinal bacteria.
• Excretion: Niacin that is consumed in excess is methylated and transformed into N1-methyl-nicotinamide in the liver. The 2- and 4-pyridone oxidation products of N1-methyl-nicotinamide contribute to the excretion. The two main substances excreted in the urine are N1-methyl-nicotinamide and its pyridone derivative, approximately 60-88% as an unchanged drug.

• https://www.ncbi.nlm.nih.gov/books/NBK541036/
• https://www.ncbi.nlm.nih.gov/books/NBK114304/
• https://ods.od.nih.gov/factsheets/Niacin-Consumer/
• https://ods.od.nih.gov/factsheets/Niacin-HealthProfessional/