GLUCOLIN COMBINATION PRODUCT POWDER FOR RECONSTITUTION

Indications

• Vitamin D deficiency
• Rickets
• Osteomalacia
• Osteoporosis
• Hypoparathyroidism

Dosage

Adults: The usual adult dose for vitamin D deficiency is 800 to 2000 IU daily, depending on the severity of deficiency and clinical condition. Higher doses may be used under medical supervision.

Mechanism of action

Cholecalciferol is converted to its active forms, 25-hydroxyvitamin D in the liver and 1,25-dihydroxyvitamin D in the kidneys. These metabolites enhance the intestinal absorption of calcium and phosphorus, increase serum calcium levels, and mobilize these minerals from bone. This process is regulated by parathyroid hormone, which influences calcium and phosphate metabolism, particularly in the kidneys.

Pharmacodynamics

The pharmacodynamics of cholecalciferol involve its conversion to active metabolites that play a significant role in calcium and phosphorus homeostasis. The metabolites facilitate intestinal absorption of these minerals, promote bone mineralization, and influence renal reabsorption. The onset of action occurs within 10 to 24 hours following administration, as metabolic activation is required for its biological effects.

Pharmacokinetics

Cholecalciferol is absorbed in the gastrointestinal tract, and its absorption is enhanced by the presence of dietary fats. It is transported in the bloodstream bound to vitamin D-binding protein. Once in the liver, it undergoes hydroxylation to form 25-hydroxyvitamin D, which is further converted in the kidneys to the active form, 1,25-dihydroxyvitamin D. The elimination half-life of cholecalciferol varies, typically spanning several days, and it is primarily excreted in bile and urine.

Adverse effects

• Hypercalcemia
• Hypercalciuria
• Nausea
• Vomiting
• Constipation
• Weakness
• Fatigue

Interactions

• May enhance the effects of thiazide diuretics, leading to increased risk of hypercalcemia
• Anticonvulsants may increase metabolism of vitamin D, leading to reduced effectiveness
• Cholestyramine may reduce absorption of vitamin D

Precautions

• Monitor serum calcium levels in patients with renal impairment
• Caution in patients with a history of hypercalcemia or hyperparathyroidism
• Use with caution in patients taking other medications that affect calcium metabolism

Pregnancy

Cholecalciferol can be used during pregnancy if indicated, as vitamin D is essential for fetal bone development.

Breast-feeding

Cholecalciferol is excreted in breast milk, but is generally considered safe during breastfeeding.

Storage

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

Formulations

• Capsules
• Tablets
• Liquid formulations

Indications

• Hypoglycemia
• Caloric supplementation in patients unable to eat
• Fluid replacement therapy
• Parenteral nutrition

Dosage

Children: Paediatric doses must be determined based on clinical condition and specific needs. Refer to the BNF for Children for appropriate dosing information.

Adults: The dosage of dextrose in adults varies based on clinical condition and route of administration. For hypoglycemia, intravenous dextrose 50% (D50W) is commonly administered. Refer to the BNF for specific dosing guidelines.

Mechanism of action

Dextrose supplies energy to tissues by generating ATP and NADH through glycolysis, where glucose is phosphorylated by hexokinase to form glucose 6-phosphate. This activates glucose for breakdown, ultimately converting glucose into energy molecules. Dextrose also plays a role in gene transcription, enzyme activity, and hormone secretion, regulating glucose homeostasis and cellular metabolic integrity.

Pharmacodynamics

Blood glucose acts as a crucial energy source for cellular activities and functions as a signaling molecule. It is oxidized into carbon dioxide and water, producing energy through glycolysis, the citric cycle, and oxidative phosphorylation. Dextrose can be converted into fat for energy storage and is stored as glycogen in the liver and muscles. Its administration, particularly orally, enhances insulin secretion due to stimulation of incretin hormones.

Pharmacokinetics

Dextrose is rapidly absorbed in the gastrointestinal tract, leading to a quick elevation of blood glucose levels. It is distributed throughout the body and can be utilized by various tissues for energy. The metabolism of dextrose primarily occurs in the liver, where it can be stored as glycogen or converted into fat. Renal excretion may occur when blood glucose levels are excessively high.

Adverse effects

• Hyperglycemia
• Fluid overload
• Hypokalemia
• Thrombophlebitis at injection site

Interactions

• Corticosteroids may increase blood glucose levels
• Beta-blockers may mask symptoms of hypoglycemia
• Diuretics may cause electrolyte imbalances

Precautions

• Use with caution in patients with diabetes mellitus
• Monitor blood glucose levels regularly
• Use cautiously in patients with renal impairment or heart failure

Pregnancy

Dextrose is generally considered safe for use during pregnancy when clinically indicated, but should be used with caution.

Breast-feeding

Dextrose can be used during breastfeeding as it is a natural sugar found in breast milk.

Storage

Store at room temperature, away from direct sunlight, and protect from freezing.

Formulations

• Dextrose 5% solution for infusion
• Dextrose 10% solution for infusion
• Dextrose 50% solution for injection
• Oral dextrose tablets

Indications

• Constipation
• Topical moisturizer for dry skin
• Ocular lubricant in eye drops

Dosage

Children: Refer to BNF for Children for specific dosing based on age and weight.

Adults: Refer to clinical guidelines for specific dosing based on the formulation and indication.

Mechanism of action

Glycerol acts as an osmotic agent, drawing water into the intestines, which helps to soften stools and promote bowel movements. It increases the osmotic pressure in the intestinal lumen, aiding in the treatment of constipation. Additionally, glycerol may provide hydration to the skin and mucous membranes due to its hygroscopic properties.

Pharmacodynamics

Glycerol has a low molecular weight and is easily absorbed by the body. Its osmotic effects help to increase the water content in the intestines, facilitating stool passage. In topical applications, glycerol enhances skin hydration, improving skin barrier function and reducing transepidermal water loss.

Pharmacokinetics

Glycerol is absorbed from the gastrointestinal tract and distributed throughout the body. It is metabolized primarily in the liver, where it can be converted into glucose or fatty acids. The elimination of glycerol occurs mainly through renal excretion, with a half-life of approximately 1.5 to 3 hours. It has a volume of distribution of about 0.4 to 0.6 L/kg.

Pregnancy

Glycerol is generally considered safe for use during pregnancy, but it is advisable to consult a healthcare provider before use.

Breast-feeding

Glycerol is excreted in breast milk in small amounts, and caution should be exercised when administering it to nursing mothers.

Storage

Store at room temperature, away from light and moisture. Keep out of reach of children.

Formulations

• Glycerol oral solution
• Glycerol suppositories
• Glycerol topical preparations

Indications

• Nutritional supplementation
• Support in metabolic disorders
• Potential use in sports nutrition

Dosage

Children: Refer to the BNF for Children for appropriate dosing recommendations.

Adults: Refer to the BNF for specific dosing guidelines.

Mechanism of action

Glycerophosphate serves as a substrate for the synthesis of phospholipids and triglycerides. It is metabolized to dihydroxyacetone phosphate, which is involved in glycolysis and gluconeogenesis, thereby participating in energy production. It may also promote the formation of ATP, enhancing cellular energy availability.

Pharmacodynamics

Glycerophosphate functions in cellular metabolism as a key intermediate in the synthesis of nucleotides and phospholipids. It aids in the regulation of osmotic balance and may influence cell signaling pathways, including those associated with growth and differentiation.

Pharmacokinetics

Glycerophosphate is absorbed in the gastrointestinal tract and is distributed throughout body tissues. It is metabolized primarily in the liver and muscle tissues, with its metabolites being excreted through urine. The half-life of glycerophosphate is variable based on tissue distribution and metabolic demand.

Pregnancy

There is no established safety profile for glycerophosphate use in pregnancy. Consult relevant guidelines and literature before prescribing.

Breast-feeding

Safety during breastfeeding has not been established. Caution is advised when administering to nursing mothers.

Storage

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

Formulations

• {'formulation': 'Glycerophosphate oral solution', 'strength': None}
• {'formulation': 'Glycerophosphate injection', 'strength': None}

Mechanism of action

Most individuals naturally generate adequate amounts of vitamin D through ordinary dietary intake of vitamin D (in some foods like eggs, fish, and cheese) and natural photochemical conversion of the vitamin D3 precursor 7-dehydrocholesterol in the skin via exposure to sunlight. Conversely, vitamin D deficiency can often occur from a combination of insufficient exposure to sunlight, inadequate dietary intake of vitamin D, genetic defects with endogenous vitamin D receptor, or even severe liver or kidney disease. Such deficiency is known for resulting in conditions like rickets or osteomalacia, all of which reflect inadequate mineralization of bone, enhanced compensatory skeletal demineralization, resultant decreased calcium ion blood concentrations, and increases in the production and secretion of parathyroid hormone. Increases in parathyroid hormone stimulate the mobilization of skeletal calcium and the renal excretion of phosphorus. This enhanced mobilization of skeletal calcium leads towards porotic bone conditions. Ordinarily, while vitamin D3 is made naturally via photochemical processes in the skin, both itself and vitamin D2 can be found in various food and pharmaceutical sources as dietary supplements. The principal biological function of vitamin D is the maintenance of normal levels of serum calcium and phosphorus in the bloodstream by enhancing the efficacy of the small intestine to absorb these minerals from the diet. At the liver, vitamin D3 or D2 is hydroxylated to 25-hydroxyvitamin D and then finally to the primary active metabolite 1,25-dihydroxyvitamin D in the kidney via further hydroxylation. This final metabolite binds to endogenous vitamin d receptors, which results in a variety of regulatory roles - including maintaining calcium balance, the regulation of parathyroid hormone, the promotion of the renal reabsorption of calcium, increased intestinal absorption of calcium and phosphorus, and increased calcium and phosphorus mobilization of calcium and phosphorus from bone to plasma to maintain balanced levels of each in bone and the plasma. In particular, calcitriol interacts with vitamin D receptors in the small intestine to enhance the efficiency of intestinal calcium and phosphorous absorption from about 10-15% to 30-40% and 60% increased to 80%, respectively. Furthermore, calcitriol binds with vitamin D receptors in osteoblasts to stimulate a receptor activator of nuclear factor kB ligand (or RANKL) which subsequently interacts with receptor activator of nuclear factor kB (NFkB) on immature preosteoclasts, causing them to become mature bone-resorbing osteoclasts. Such mature osteoclasts ultimately function in removing calcium and phosphorus from bone to maintain blood calcium and phosphorus levels. Moreover, calcitriol also stimulates calcium reabsorption from the glomerular filtrate in the kidneys. Additionally, it is believed that when calcitriol binds with nuclear vitamin D receptors, that this bound complex itself binds to retinoic acid X receptor (RXR) to generate a heterodimeric complex that consequently binds to specific nucleotide sequences in the DNA called vitamin D response elements. When bound, various transcription factors attach to this complex, resulting in either up or down-regulation of the associated gene's activity. It is thought that there may be as much as 200 to 2000 genes that possess vitamin D response elements or that are influenced indirectly to control a multitude of genes across the genome. It is in this way that cholecalciferol is believed to function in regulating gene transcription associated with cancer risk, autoimmune disorders, and cardiovascular disease linked to vitamin D deficiency. In fact, there has been some research to suggest calcitriol may also be able to prevent malignancies by inducing cellular maturation and inducing apoptosis and inhibiting angiogenesis, exhibit anti-inflammatory effects by inhibiting foam cell formation and promoting angiogenesis in en

Pharmacodynamics

The in vivo synthesis of the predominant two biologically active metabolites of vitamin D occurs in two steps. The first hydroxylation of vitamin D3 cholecalciferol (or D2) occurs in the liver to yield 25-hydroxyvitamin D while the second hydroxylation happens in the kidneys to give 1, 25-dihydroxyvitamin D. These vitamin D metabolites subsequently facilitate the active absorption of calcium and phosphorus in the small intestine, serving to increase serum calcium and phosphate levels sufficiently to allow bone mineralization. Conversely, these vitamin D metabolites also assist in mobilizing calcium and phosphate from bone and likely increase the reabsorption of calcium and perhaps also of phosphate via the renal tubules. There exists a period of 10 to 24 hours between the administration of cholecalciferol and the initiation of its action in the body due to the necessity of synthesis of the active vitamin D metabolites in the liver and kidneys. It is parathyroid hormone that is responsible for the regulation of such metabolism at the level of the kidneys.

Mechanism of action

Glucose supplies most of the energy to all tissues by generating energy molecules ATP and NADH during a series of metabolism reactions called glycolysis. Glycolysis can be divided into two main phases where the preparatory phase is initiated by the phosphorylation of glucose by hexokinase to form glucose 6-phosphate. The addition of the high-energy phosphate group activates glucose for the subsequent breakdown in later steps of glycolysis and is the rate-limiting step. Products end up as substrates for following reactions, to ultimately convert C6 glucose molecule into two C3 sugar molecules. These products enter the energy-releasing phase where the total of 4ATP and 2NADH molecules are generated per one glucose molecule. The total aerobic metabolism of glucose can produce up to 36 ATP molecules. These energy-producing reactions of glucose are limited to D-glucose as L-glucose cannot be phosphorylated by hexokinase. Glucose can act as precursors to generate other biomolecules such as vitamin C. It plays a role as a signaling molecule to control glucose and energy homeostasis. Glucose can regulate gene transcription, enzyme activity, hormone secretion, and the activity of glucoregulatory neurons. The types, number, and kinetics of glucose transporters expressed depends on the tissues and fine-tunes glucose uptake, metabolism, and signal generation to preserve cellular and whole body metabolic integrity. Vascular calcification is a hallmark of type 2 diabetes. Glucose stimulates calcification in culture of vascular smooth muscle cells (VSMCs) but the underlying mechanisms remain obscure. We observed that high glucose levels stimulated mouse and human VSMC trans-differentiation into chondrocytes, with increased levels of Sox9, type II collagen, glycosaminoglycan and Runx2 expression, and increased alkaline phosphatase activity and mineralization. These effects were associated with increased expression of IL-1beta, which stimulated alkaline phosphatase and calcification, suggesting that glucose induces chondrocyte differentiation of VSMCs, possibly through IL-1beta activation.

Pharmacodynamics

Blood glucose is an obligatory energy source for humans involved in various cellular activities, and it also acts as a signaling molecule for diverse glucose-sensing molecules and proteins. Glucose undergoes oxidation into carbon dioxide, water, and yields energy molecules in the process of glycolysis and subsequent citric cycle and oxidative phosphorylation. Glucose is readily converted into fat in the body which can be used as a source of energy as required. Under a similar conversion into storage of energy, glucose is stored in the liver and muscles as glycogen. Glucose stores are mobilized in a regulated manner, depending on the tissues' metabolic demands. Oral glucose tablets or injections serve to increase the supply of glucose and oral glucose administration is more effective in stimulating insulin secretion because it stimulates the incretin hormones from the gut, which promotes insulin secretion.