NEUROVEN CAPSULES

Indications

• Vitamin deficiency syndromes (e.g., scurvy for vitamin C deficiency, rickets for vitamin D deficiency)
• Support for immune function
• Antioxidant support
• Bone health maintenance
• Vision health
• Energy metabolism support

Dosage

Children: Refer to the BNF for Children for specific vitamin dosing guidelines, which depend on age and nutritional requirements.

Adults: Refer to specific vitamin guidelines as dosage varies significantly depending on the type of vitamin and individual needs.

Mechanism of action

Vitamins function primarily as coenzymes or precursors for coenzymes in enzymatic reactions. For instance, B vitamins are involved in energy metabolism, while vitamins A, C, D, E, and K support various physiological functions including vision, antioxidant activity, calcium regulation, and blood clotting. Each vitamin has a unique mechanism of action based on its structure and role in the body.

Pharmacodynamics

Vitamins exert their effects at the cellular level, influencing metabolic pathways, gene expression, and immune responses. For example, vitamin D regulates calcium and phosphate homeostasis, while vitamin A is crucial for vision and immune function. Deficiencies in vitamins can lead to a range of disorders, highlighting their importance in maintaining health.

Pharmacokinetics

The pharmacokinetics of vitamins vary widely. Fat-soluble vitamins (A, D, E, and K) are stored in liver and adipose tissues and can be released into circulation as needed. Water-soluble vitamins (B-complex and C) are not stored and must be consumed regularly, with excess amounts excreted in urine. Absorption rates, half-lives, and distribution can also differ based on the specific vitamin and individual metabolic factors.

Interactions

• tretinoin+vitamin: Severe (increases risk of vitamin toxicity)
• retinoids+vitamin: Severe (increases risk of vitamin toxicity)
• retinoids+vitamin: Moderate (increases risk of toxicity)
• carbamazepine+vitamin: Unknown (decreases effects)
• cobicistat+vitamin: Unknown (increases exposure)
• vitamin D substances+digoxin: Unknown (increases risk of toxicity)
• idelalisib+vitamin: Unknown (increases exposure)
• clarithromycin+vitamin: Unknown (increases exposure)

Pregnancy

Consult healthcare professional before use. Vitamin supplementation during pregnancy should be carefully managed to avoid hypervitaminosis.

Breast-feeding

Consult healthcare professional before use. Some vitamins can pass into breast milk and may affect the infant.

Storage

Store in a cool, dry place, away from direct sunlight. Ensure it is kept out of reach of children.

Formulations

• {'name': 'Vitamin A', 'form': 'Capsule', 'strength': '10000 IU'}
• {'name': 'Vitamin D', 'form': 'Tablet', 'strength': '1000 IU'}
• {'name': 'Vitamin E', 'form': 'Softgel', 'strength': '400 IU'}

Indications

• Vitamin B12 deficiency
• Pernicious anemia
• Megaloblastic anemia due to folate deficiency
• Neuropathy due to vitamin B12 deficiency
• Dietary deficiency in vegetarians and elderly individuals

Dosage

Children: Refer to BNF for Children for specific dosing recommendations.

Adults: Refer to clinical guidelines or BNF for specific dosing recommendations.

Mechanism of action

Vitamin B12 acts as a cofactor for two essential enzymes: methionine synthase and L-methylmalonyl-CoA mutase. Methionine synthase is involved in the conversion of homocysteine to methionine, an important amino acid, while L-methylmalonyl-CoA mutase is crucial in the metabolism of certain fatty acids and amino acids. The deficiency of vitamin B12 disrupts these metabolic pathways, leading to the clinical manifestations of deficiency.

Pharmacodynamics

Vitamin B12 is vital for the production of myelin, the protective sheath surrounding nerves, thereby playing a significant role in neurological health. It also supports the formation of red blood cells and is involved in the metabolism of carbohydrates and fats, influencing energy production in the body.

Pharmacokinetics

Vitamin B12 is absorbed in the ileum of the intestine, where it binds to intrinsic factor, a glycoprotein secreted by the stomach. This complex is then transported into the bloodstream. The vitamin is stored primarily in the liver, with a large reserve that can last for years. The body excretes excess vitamin B12 through the urine, and its half-life can extend up to several days depending on body stores.

Contra-indications

• Hypersensitivity to vitamin B12 or cobalt
• Leber's disease (hereditary optic neuropathy)

Adverse effects

• Headache
• Nausea
• Diarrhea
• Itching or rash
• Anaphylactic reactions in sensitive individuals

Interactions

• Chloramphenicol may inhibit the therapeutic effect of vitamin B12
• Prolonged use of proton pump inhibitors may decrease absorption
• Metformin may decrease vitamin B12 absorption with long-term use

Precautions

• Monitor for signs of deficiency in patients with malabsorption syndromes
• Use with caution in patients with severe renal impairment
• Caution in patients with a history of hypersensitivity reactions

Pregnancy

Vitamin B12 is generally considered safe during pregnancy, as it is essential for fetal development. However, it is important to ensure adequate intake.

Breast-feeding

Vitamin B12 is excreted in breast milk; adequate maternal intake is crucial for breastfeeding infants.

Storage

Store in a cool, dry place away from light. Keep out of reach of children.

Formulations

• Injectable solution
• Oral tablets
• Sublingual tablets
• Nasal spray