Naso B12 Nasal Spray

Indications

• Constipation
• Bowel cleansing

Dosage

Children: Child 1–11 months: 1 g as required, Child 1–11 years: 2 g as required, Child 12–17 years: 4 g as required.

Adults: 4 g as required, usually administered rectally.

Mechanism of action

When administered rectally, glycerol exerts a hygroscopic and/or local irritant action, drawing water from the tissues into the feces and reflexively stimulating evacuation. It decreases intraocular pressure by creating an osmotic gradient between the blood and intraocular fluid, causing fluid to move from the aqueous and vitreous humors into the bloodstream. Glycerol is classified as a hyperosmotic laxative and may also have lubricating and fecal softening effects.

Pharmacodynamics

Glycerol is commonly classified as an osmotic laxative, acting through its local irritant effects and possibly having lubricating and fecal softening actions. Glycerol suppositories usually produce effects within 15 to 30 minutes, providing quick relief from constipation.

Pharmacokinetics

Glycerol is rapidly absorbed through the gastrointestinal tract. It is metabolized in the liver and other tissues, with a half-life that varies depending on the route of administration. Following rectal administration, glycerol is primarily excreted in urine. The pharmacokinetics may vary based on dosage forms and individual patient factors.

Contra-indications

• Acute abdominal conditions
• Acute inflammatory bowel disease
• Intestinal obstruction
• Severe dehydration

Adverse effects

• Abdominal cramps
• Asthenia
• Gastrointestinal disorders
• Hypermagnesaemia
• Skin reactions
• Urine discolouration

Precautions

• Avoid prolonged contact with skin, especially in incontinent patients or infants wearing nappies due to the risk of irritation and excoriation.
• Excessive use may cause diarrhea and related effects such as hypokalaemia.

Pregnancy

Manufacturers advise avoidance due to limited information available.

Breast-feeding

Manufacturers advise avoidance as there is no information available.

Storage

Store at room temperature, away from direct sunlight.

Formulations

• Glycerol 1g suppositories
• Glycerol 2g suppositories
• Glycerol 4g suppositories
• Glycerol oral suspension

Indications

• Seborrhoeic dermatitis
• Dandruff
• Scalp psoriasis
• Bacterial infections affecting the scalp

Dosage

Children: For children, apply 3 times a week for 1 week, then apply twice weekly as needed. Refer to BNF for Children for further details.

Adults: Apply to the affected area as directed, typically 1-3 times weekly depending on the condition being treated. Refer to specific product guidelines for detailed dosing.

Mechanism of action

Benzalkonium chloride exerts its antimicrobial effect by disrupting the cell membrane of microorganisms, leading to leakage of cellular contents and ultimately cell death. This is facilitated by its cationic nature, which allows it to bind to negatively charged bacterial surfaces.

Pharmacodynamics

Benzalkonium chloride demonstrates rapid bactericidal activity, with effectiveness observed against gram-positive and gram-negative bacteria, fungi, and some viruses. Its antiseptic properties may be enhanced in the presence of moisture and are typically influenced by the concentration of the solution used.

Pharmacokinetics

Benzalkonium chloride is poorly absorbed through the skin. After topical application, it remains primarily at the site of application, where it exerts localized effects. Systemic absorption is minimal, and it is primarily eliminated through the skin and urine. However, specific pharmacokinetic data may vary based on formulation and application site.

Pregnancy

Benzalkonium chloride should be used with caution during pregnancy. Refer to specific guidelines or consult a healthcare professional.

Breast-feeding

Benzalkonium chloride should be used with caution while breastfeeding. Refer to specific guidelines or consult a healthcare professional.

Storage

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

Formulations

• Shampoo
• Soap or detergent
• Topical solution

Indications

• Disinfection of surfaces
• Antiseptic for skin
• Preservative in pharmaceuticals
• Treatment of minor cuts and abrasions

Dosage

Children: Refer to the BNF for Children for specific dosing recommendations in pediatric populations.

Adults: Refer to the BNF for specific formulations and concentrations as doses may vary based on the application and preparation.

Mechanism of action

The bactericidal action of benzalkonium chloride is believed to result from the disruption of intermolecular interactions, which leads to the dissociation of cellular membrane lipid bilayers in bacteria. This disruption compromises cellular permeability, causing leakage of vital cellular contents. Moreover, the agent can deactivate important molecular complexes such as enzymes that regulate various respiratory and metabolic activities within the cells. Cationic surfactants like benzalkonium chloride can thus effectively disrupt critical intermolecular interactions and tertiary structures in biochemical systems, impairing bacterial function.

Pharmacodynamics

Benzalkonium chloride is classified as a biocidal agent with a relatively long duration of action. It exhibits a spectrum of activity against various microorganisms, including bacteria, certain viruses, fungi, and protozoa; however, it is ineffective against bacterial spores. The agent tends to demonstrate greater efficacy against gram-positive bacteria compared to gram-negative ones. The mode of action can be bacteriostatic (preventing growth) or bactericidal (killing bacteria), depending on its concentration. The activity of benzalkonium chloride is generally stable across different pH levels but is enhanced at elevated temperatures and with extended exposure.

Pharmacokinetics

The pharmacokinetic properties of benzalkonium chloride, including absorption, distribution, metabolism, and excretion, are not fully characterized. Its topical application limits systemic exposure, and it primarily exerts localized effects at the site of application. The duration of action and efficacy may be influenced by the formulation and concentration used.

Pregnancy

Benzalkonium chloride is generally considered safe for use during pregnancy when applied topically, but systemic absorption should be minimized. Always consult a healthcare provider for use during pregnancy.

Breast-feeding

Benzalkonium chloride is considered safe for topical application during breastfeeding, but care should be taken to avoid exposure to the infant. Consultation with a healthcare provider is recommended.

Storage

Store at room temperature, away from moisture and heat. Keep in a tightly closed container, protected from light.

Formulations

• Topical solution
• Disinfectant wipes
• Liquid antiseptics

Indications

• Acidulant in food and beverages
• Preservative in pharmaceutical formulations
• pH adjuster in various chemical preparations

Dosage

Children: Refer to product-specific guidelines for appropriate dosing based on formulation and indication.

Adults: Refer to product-specific guidelines for appropriate dosing based on formulation and indication.

Mechanism of action

Citric acid acts by chelating metal ions, which can enhance the solubility of certain compounds and improve their bioavailability. It also contributes to the acidity of the environment, which can influence enzymatic activity and metabolic pathways, particularly in the degradation of citronellol.

Pharmacodynamics

Citric acid exhibits mild pharmacological effects primarily attributed to its role in metabolic processes. It aids in the regulation of pH levels, which can impact enzymatic reactions and biochemical pathways. The acid's chelating properties may help to reduce the toxicity of certain metal ions in biological systems.

Pharmacokinetics

Citric acid is rapidly absorbed after oral administration and is metabolized in the liver. It undergoes conversion to various metabolites in the citric acid cycle, contributing to energy production. The elimination primarily occurs through urine, with minimal accumulation in the body.

Pregnancy

Citric acid is generally regarded as safe during pregnancy when used in food amounts. However, consult a healthcare provider for advice on medicinal use.

Breast-feeding

Citric acid is considered safe during breastfeeding when consumed in food amounts. For medicinal use, consult a healthcare provider.

Storage

Store in a cool, dry place away from direct sunlight.

Indications

• Solvent for poorly soluble drugs
• Enhancement of drug bioavailability in formulations

Dosage

Children: Refer to specific product guidelines for dosing, as glycofurol is primarily used as an excipient and does not have established dosing regimens.

Adults: Refer to specific product guidelines for dosing, as glycofurol is primarily used as an excipient and does not have established dosing regimens.

Mechanism of action

Glycofurol acts as a solvent and stabilizing agent, enhancing the solubility and bioavailability of certain drugs. It does not have a specific pharmacological action on biological targets but rather facilitates the delivery of other active pharmaceutical ingredients through its properties as a solvent.

Pharmacodynamics

As a solvent, glycofurol aids in the dissolution of hydrophobic drugs, improving their absorption and effectiveness. Its role is primarily supportive, enhancing the pharmacological effects of co-administered compounds rather than exhibiting direct therapeutic activity itself.

Pharmacokinetics

Glycofurol is absorbed when administered and is metabolized in the liver. Its elimination half-life and specific metabolic pathways have not been extensively characterized, but it is generally expected to be eliminated via renal pathways. The exact pharmacokinetic profile may vary depending on the formulation and the presence of other active ingredients.

Pregnancy

Glycofurol should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. There is insufficient data on its safety in pregnancy.

Breast-feeding

It is unknown whether glycofurol is excreted in human milk. Caution should be exercised when administering to breastfeeding women.

Storage

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

Dosage

Children: Refer to specific clinical guidelines for dosing in children, as no standard paediatric dosage is specified in the provided resources.

Adults: Refer to specific clinical guidelines for dosing, as no standard adult dosage is specified in the provided resources.

Mechanism of action

Ethylene glycol toxicity results from its metabolism to glycolic acid and other toxic metabolites. Glycolate accumulates in the body and is eliminated more slowly than ethylene glycol itself. The renal excretion of both compounds plays a crucial role in their elimination, accounting for a significant portion of the administered dose.

Pharmacodynamics

The pharmacodynamics of glycolate are closely tied to its role as a metabolite of ethylene glycol. Its accumulation can lead to metabolic acidosis, although minimal clinical effects have been observed at low doses. The relationship between glycolate and ethylene glycol indicates that glycolate may contribute to the overall toxic effects of ethylene glycol ingestion.

Pharmacokinetics

The pharmacokinetics of glycolate indicate that it reaches peak plasma levels between 4-6 hours after the administration of ethylene glycol. The elimination half-life of ethylene glycol is approximately 1.7 hours in rats and 3.4 hours in dogs. Glycolate is predominantly eliminated through renal excretion, with about 5% of the dose being excreted unchanged.

Pregnancy

There is limited data on the safety of glycolate in pregnancy. Caution is advised.

Breast-feeding

Data on the excretion of glycolate in human milk is not available. Caution is advised.

Storage

Store at room temperature, away from light and moisture.

Indications

• Vitamin B12 deficiency
• Peripheral neuropathy
• Megaloblastic anemia
• Homocystinuria

Dosage

Children: Refer to the BNF for Children for appropriate paediatric dosing information.

Adults: Refer to the BNF for specific dosing recommendations based on the indication.

Mechanism of action

Methylcobalamin functions as a coenzyme in the conversion of homocysteine to methionine, facilitating the synthesis of S-adenosylmethionine (SAMe). SAMe is a critical methyl donor in numerous biochemical reactions, including the methylation of DNA and proteins. Additionally, methylcobalamin is essential for the regeneration of folate, impacting DNA synthesis and repair. It also promotes nerve regeneration and repair, making it beneficial in conditions involving nerve damage.

Pharmacodynamics

Methylcobalamin exhibits neuroprotective properties by enhancing nerve growth factor (NGF) synthesis and supporting neuronal survival. It aids in the reduction of neuropathic pain and may improve neurological function in patients with vitamin B12 deficiency. The compound's role in methylation processes further influences cellular metabolism, contributing to overall health.

Pharmacokinetics

Methylcobalamin is absorbed in the intestines, and its bioavailability can be influenced by the presence of intrinsic factor, which is necessary for vitamin B12 absorption. Once absorbed, it is distributed throughout the body, particularly in the liver, kidneys, and nervous tissue. The elimination half-life of methylcobalamin is variable, and the compound is primarily excreted in the urine as metabolites. Storage and transport within the body are facilitated by transcobalamin II, a specific transport protein.

Adverse effects

• Headache
• Nausea
• Diarrhea
• Dizziness
• Rash
• Itching

Interactions

• Alcohol may decrease the absorption of methylcobalamin
• Certain medications that affect vitamin B12 levels

Precautions

• Patients with Leber's disease should use with caution
• Monitor for signs of hypersensitivity

Pregnancy

Methylcobalamin is generally considered safe during pregnancy as it is a form of vitamin B12, but consult a healthcare provider for personalized advice.

Breast-feeding

Methylcobalamin is excreted in breast milk, but is considered safe for use during breastfeeding; consult a healthcare provider for personalized advice.

Storage

Store in a tightly closed container at room temperature, away from moisture and heat.

Formulations

• Oral tablets
• Sublingual tablets
• Injectable solution

Indications

• Nutritional supplementation
• Energy source in enteral nutrition
• Excipient in pharmaceutical formulations

Dosage

Children: Refer to specific guidelines or product inserts for dosing information, as it can vary based on the context of use.

Adults: Refer to specific guidelines or product inserts for dosing information, as it can vary based on the context of use.

Mechanism of action

Starch is broken down into glucose units by enzymes such as amylase during digestion. The glucose is then absorbed in the intestines and utilized for energy production in the body's cells. This pathway involves hydrolysis of the glycosidic bonds, converting starch into simpler sugars.

Pharmacodynamics

Starch primarily serves as an energy source. Its digestion and absorption lead to an increase in blood glucose levels, which provides energy for metabolic processes. In this context, it plays a crucial role in maintaining energy homeostasis in the body.

Pharmacokinetics

Starch is not absorbed in its polymeric form; it must first be enzymatically hydrolyzed into simpler sugars such as maltose and glucose. The digestion and absorption of starch occur predominantly in the small intestine, with glucose being readily absorbed into the bloodstream. The rate of absorption can vary depending on the type of starch and its physical form.

Adverse effects

• Allergic reactions
• Gastrointestinal discomfort
• Diarrhea
• Constipation

Precautions

• Use with caution in individuals with known allergies to starch or starch derivatives
• Monitor for gastrointestinal symptoms in patients with a history of digestive disorders

Pregnancy

Starch is generally considered safe for use during pregnancy. However, it should be consumed in moderation as part of a balanced diet.

Breast-feeding

Starch is deemed safe for nursing mothers when used in moderation as part of a balanced diet.

Storage

Store in a cool, dry place away from moisture and direct sunlight.

Formulations

• Powder
• Granules
• Tablets
• Suspensions

Mechanism of action

When administered rectally, glycerin exerts a hygroscopic and/or local irritant action, drawing water from the tissues into the feces and reflexively stimulating evacuation. Glycerin decreases intraocular pressure by creating an osmotic gradient between the blood and intraocular fluid, causing fluid to move out of the aqueous and vitreous humors into the bloodstream. Glycerin (glycerol) and sorbitol are hyperosmotic laxatives. When administered rectally, glycerin and sorbitol exert a hygroscopic and/or local irritant action, drawing water from the tissues into the feces and reflexly stimulating evacuation. The extent to which the simple physical distention of the rectum and the hygroscopic and/or local irritant actions are responsible for the laxative effects of some of these drugs is not known. Only extremely high oral doses of sorbitol (25 g daily) or glycerin exert laxative action. /Glycerin/ decreases intraocular pressure by creating an osmotic gradient between the blood and intraocular fluid, causing fluid to move out of the aqueous and vitreous humors into the bloodstream. The physicochemical effects of a series of alkanols, alkanediols and glycerol on erythrocyte shape and hemolysis at 4 and 20 degrees C were examined. We calculated the dielectric constant of the incubation medium, Ds, and the dielectric constant of the erythrocyte membrane Dm in the presence of organic solutes. The ratio Ds/Dm = -38.48 at 20 degrees C defines the normal biconcave shape in a medium without hemolytic agents. A decrease in Ds/Dm favors externalization or internalization with consequent hemolysis. Alkanols and alkanediols convert biconcave erythrocytes into echinocytes, which is accompanied by an increase in the projected surface area. Glycerol converts biconcave erythrocytes into stomatocytes, which was accompanied by a marginal decrease in the projected surface area. Progressive externalization in alkanols and alkanediols or internalization in glycerol resulted in a decrease in the projected surface area and the formation of smooth spheres. The degree of shape change induced was related to the degree of hemolysis and the ratio Ds/Dm. A decrease in temperature reduced both the degree of shape change and hemolysis. .../Thus/ physicochemical toxicity may be a result of a temperature dependent hydrophobic interaction between the organic solutes and the membrane and is best interpreted by the ability of the solutes to change Ds and Dm.

Pharmacodynamics

Glycerin is commonly classified as an osmotic laxative but may act additionally or alternatively through its local irritant effects; it may also have lubricating and fecal softening actions. Glycerin suppositories usually work within 15 to 30 minutes.

Mechanism of action

Although not entirely elucidated, the bactericidal action of benzalkonium chloride is believed to be due to the disruption of intermolecular interactions. Such disruption can cause the dissociation of cellular membrane lipid bilayers of bacteria, resulting in compromised cellular permeability control and the leakage of important cellular contents. Additionally, other important molecular complexes like enzymes which control the maintenance of a great range of respiratory and metabolic cellular activities, are also susceptible to such deactivation. Consequently, a variety of critical intermolecular interactions and tertiary structures in very highly specific biochemical systems that allow bacterial agents to function normally can be readily disrupted or deactivated by cationic surfactants like benzalkonium chloride..

Pharmacodynamics

Benzalkonium chloride solutions are generally categorized as biocidal agents with relative long durations of action. Their spectrum of activity has been demonstrated against bacteria, to some viruses, fungi, and protozoa, although bacterial spores are treated as being resistant to the agent. Additionally, the agent generally shows more activity against gram-positive than gram-negative bacteria. Finally, solutions of benzalkonium chloride are bacteriostatic or bactericidal based on their concentration. Bacteriostatic agents act to prevent further growth of bacterial organisms that are present while bactericidal agents function to kill bacteria that are present. In general, the activity of the agent is not largely affected by pH, but such activity does increase substantially at higher temperatures and prolonged exposure times.

Mechanism of action

Ethylene glycol toxicity results from its metabolism to glycolic acid and other toxic metabolites. The accumulation of glycolate and the elimination kinetics of ethylene glycol and its metabolites are not well understood, so studies with male Sprague-Dawley rats and mixed breed dogs have been carried out. Ethylene glycol was administered by gavage to rats and dogs which were placed in metabolic cages for urine and blood sample collection at timed intervals. The peak plasma level of ethylene glycol occurred at 2 hr after dosing and that of glycolate between 4-6 hr. The rate of ethylene glycol elimination was somewhat faster in rats with a half-life of 1.7 hr compared to 3.4 hr in dogs. The maximum plasma level of glycolate was greater in rats although the pattern of accumulation was similar to that in dogs. Glycolate disappeared from the plasma at the same time as ethylene glycol, suggesting a slower rate of elimination of the metabolite than that of ethylene glycol. Renal excretion of ethylene glycol was an important route for its elimination accounting for 20-30% of the dose. Renal excretion of glycolate represented about 5% of the dose. Ethylene glycol induced an immediate, but short lived diuresis compared to that in control rats. Minimal clinical effects (mild acidosis with no sedation) were noted at these doses of ethylene glycol (1-2 g/kg) in both rats and dogs. The results indicate that the toxicokinetics of ethylene glycol and glycolate were similar in both species. The effect of 0.35 to 0.8 mmol/kg glycolic acid and 1.0 to 4.4 mmol/kg sodium glycolate on cyclopropane-epinephrine induced cardiac arrhythmias was examined using dogs. Doses of 0.35 to 0.5 mmol/kg glycolic acid increased the duration of arrhythmias in the 13 dogs tested, whereas doses >0.5 mmol/kg decreased or totally eliminated the arrhythmias in each of 11 dogs. Depression was observed for many of the dogs at higher doses. Sodium glycolate was much less effective in decreasing the arrhythmias, with 3 mmol/kg being required and its action being transient.