Betadine Germicide Gargle 2%-Mint

Indications

• Skin disinfection
• Preparation of skin before injections
• Cleansing minor wounds

Dosage

Children: Apply to the skin as required; consult product literature for specific guidance.

Adults: Apply to the skin as required for disinfection.

Mechanism of action

Alcohol exerts its antiseptic effect by denaturing proteins, disrupting cell membranes, and dehydrating microbial cells, leading to cell lysis and death.

Pharmacodynamics

Alcohol has broad-spectrum antimicrobial activity, effective against bacteria, fungi, and viruses. Its efficacy is influenced by concentration, with higher concentrations generally being more effective.

Pharmacokinetics

Alcohol is rapidly absorbed through the skin and mucous membranes. It is metabolized primarily in the liver, with a half-life that varies based on the individual's metabolic rate and the amount consumed.

Contra-indications

• Concomitant use with lithium
• Regular use in neonates
• Patients with severe burns when diathermy has been preceded by application of alcoholic skin disinfectants

Adverse effects

• Eye erythema
• Punctate keratitis
• Cytotoxicity
• Eye discolouration

Interactions

• Increases risk of visual disturbances with antiepileptics
• Increases concentration with methylphenidate
• Increases risk of facial flushing and skin irritation with topical pimecrolimus
• Increases concentration with retinoids
• Increases concentration with acitretin
• Increases risk of facial flushing and skin irritation with topical tacrolimus
• Decreases antidiuretic effect with vasopressin

Precautions

• Avoid regular application to inflamed or broken skin or mucosa
• Avoid broken skin
• Flammable

Pregnancy

Sufficient iodine may be absorbed to affect the fetal thyroid in the second and third trimester.

Breast-feeding

Avoid regular or excessive use.

Storage

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

Formulations

• Betadine 2.5% dry powder spray
• Industrial methylated spirit
• Povidone-Iodine 25 mg per 1 gram

Indications

• Dehydration
• Fluid replacement
• Support for metabolic reactions
• Regulation of body temperature

Dosage

Children: Fluid requirements for children depend on age, weight, and activity level. It is crucial to monitor hydration status and adjust intake accordingly, referring to specific guidelines in the BNF for Children.

Adults: Dosage varies based on individual needs, activity level, and environmental conditions. General guidelines suggest approximately 2 to 3 liters per day for adults, considering factors like exercise and climate.

Mechanism of action

Water acts as a solvent in biological systems, enabling the dissolution and transport of nutrients and waste products. It also plays a vital role in metabolic reactions, including hydrolysis and dehydration synthesis, which are essential for cellular function.

Pharmacodynamics

Water maintains cellular integrity and supports physiological functions, including osmotic balance, acid-base equilibrium, and thermoregulation. Its role in enzymatic reactions and as a medium for biochemical processes is crucial for organismal health.

Pharmacokinetics

Water is absorbed efficiently in the gastrointestinal tract and distributed throughout the body via the bloodstream. It is excreted primarily through urine, sweat, and respiration. The body regulates water balance through mechanisms involving the kidneys, hormones, and thirst responses.

Pregnancy

Considered safe for use.

Breast-feeding

Considered safe for use.

Storage

Store in a cool, dry place away from sunlight.

Formulations

• Liquid
• Pure Water

Indications

• Prevention of postoperative nausea and vomiting
• Treatment of nausea and vomiting
• Premedication for surgical procedures

Dosage

Children: Refer to the BNF for Children for age-appropriate dosing guidelines.

Adults: Refer to the BNF for specific dosing recommendations based on the clinical context and patient condition.

Mechanism of action

Droperidol primarily acts as an antagonist at dopamine D2 receptors in the central nervous system. This blockade of dopamine receptors leads to a decrease in nausea and vomiting, as dopamine is a key neurotransmitter involved in these processes. Furthermore, droperidol may also have some affinity for other receptor types, including adrenergic and serotonin receptors, contributing to its sedative and antiemetic effects.

Pharmacodynamics

The pharmacodynamic profile of droperidol includes its ability to reduce the incidence of nausea and vomiting through central action. It can also produce sedation and anxiolytic effects, making it useful in preoperative settings. The onset of action is typically rapid, with effects observed shortly after administration. Droperidol has a dose-dependent relationship, where higher doses may lead to increased sedation and potential extrapyramidal side effects due to its dopamine antagonism.

Pharmacokinetics

Droperidol is well-absorbed after parenteral administration, with peak plasma concentrations occurring within 30 minutes to 1 hour. It is metabolized in the liver, primarily via cytochrome P450 enzymes, and has a relatively short half-life, generally ranging from 1 to 3 hours. Droperidol is excreted mainly in urine as metabolites, with less than 1% of the dose excreted unchanged. The drug's pharmacokinetic profile can be influenced by factors such as age, liver function, and concurrent medications.

Interactions

• droperidol + dopaminereceptor agonists: Severe (decreases effects)
• droperidol + levodopa: Unknown (decreases effects)

Indications

• Constipation
• Preparation for surgical or diagnostic procedures involving the rectum
• Decreasing intraocular pressure in certain ocular conditions

Dosage

Children: For children aged 2 to 6 years, 2 g to 5 g of glycerin may be used as a suppository. Children aged 6 to 12 years may use 5 g to 10 g as needed. For specific pediatric dosing, please refer to the BNF for Children.

Adults: For rectal use, 4 g to 10 g of glycerin may be administered as a suppository as needed.

Mechanism of action

When administered rectally, glycerin draws water from the tissues into the feces due to its hygroscopic action, which reflexively stimulates bowel evacuation. Additionally, glycerin creates an osmotic gradient that leads to a decrease in intraocular pressure by facilitating fluid movement from the aqueous and vitreous humors into the bloodstream.

Pharmacodynamics

Glycerin is classified as an osmotic laxative, which acts to retain water in the fecal matter, softening stools and making them easier to pass. Its local irritant effects also contribute to its laxative properties. Glycerin suppositories typically produce a bowel movement within 15 to 30 minutes of administration.

Pharmacokinetics

Glycerin is readily absorbed from the gastrointestinal tract when taken orally and is metabolized primarily in the liver. It is distributed widely throughout the body, with excretion occurring primarily via the kidneys. The onset of action for glycerin when used as a laxative is relatively quick, particularly when used rectally.

Contra-indications

• Severe dehydration
• Severe renal impairment
• Intestinal obstruction
• Appendicitis

Adverse effects

• Abdominal cramps
• Diarrhea
• Nausea
• Vomiting
• Electrolyte imbalance

Interactions

• May enhance the effects of other laxatives
• Caution with concurrent use of diuretics due to potential electrolyte imbalance

Precautions

• Use with caution in patients with renal impairment
• Monitor electrolytes in patients with prolonged use
• Not recommended for long-term use

Pregnancy

Glycerin is generally considered safe during pregnancy but should be used under medical advice.

Breast-feeding

Glycerin is excreted in breast milk in small amounts and is considered safe for use while breastfeeding.

Storage

Store at room temperature, away from moisture and heat.

Formulations

• Glycerin suppositories
• Glycerin oral solution

Indications

• Iodine deficiency
• Goiter
• Hypothyroidism
• Thyroiditis
• Fibrocystic breast disease

Dosage

Children: Refer to the BNF for Children for appropriate dosing guidelines based on age and weight.

Adults: Refer to the BNF for appropriate dosing guidelines based on condition and clinical judgment.

Mechanism of action

Molecular iodine inhibits the induction and promotion of carcinogenesis in mammary tissues and has shown beneficial effects in fibrocystic breast disease. It temporarily decreases thyroid hormone production through the acute Wolff-Chaikoff effect, followed by a return to normal hormone synthesis due to down regulation of the sodium-iodide symport. This mechanism can lead to a transient hypothyroid state in some individuals with underlying thyroid conditions.

Pharmacodynamics

Iodine is vital for the synthesis of thyroid hormones thyroxine (T4) and triiodothyronine (T3). It affects the metabolism of amine-derived hormones and plays a role in amino acid metabolism. The acute excess of iodide can lead to decreased circulating levels of T4 and T3 in susceptible individuals, while most people can escape this effect and maintain normal thyroid function.

Pharmacokinetics

Iodine is absorbed primarily in the gastrointestinal tract and is distributed throughout the body, particularly in the thyroid gland, where it is concentrated for hormone synthesis. The kidney plays a significant role in the excretion of excess iodine. The half-life of iodine in the body varies and can be influenced by dietary intake and underlying health conditions.

Adverse effects

• Hypothyroidism
• Hyperthyroidism
• Iodine allergy
• Gastrointestinal disturbances

Interactions

• Thyroid hormones
• Antithyroid drugs
• Lithium
• Diuretics

Precautions

• Use with caution in patients with thyroid dysfunction
• Monitor thyroid function periodically during treatment
• Pregnant or breastfeeding women should consult a healthcare provider before use

Pregnancy

Iodine is essential for fetal thyroid hormone synthesis, but excessive iodine intake should be avoided.

Breast-feeding

Iodine is excreted in breast milk; consult a healthcare provider regarding supplementation.

Storage

Store in a cool, dry place away from light.

Formulations

• Iodine solution
• Iodine tincture
• Potassium iodide tablets

Indications

• Topical analgesic for muscle and joint pain
• Cough suppressant in cough drops and lozenges
• Relief of minor throat irritation
• Cooling agent in various cosmetic and personal care products

Dosage

Children: Refer to BNF for Children for specific dosing guidelines, as doses may vary based on age and formulation.

Adults: For topical use, apply a thin layer to the affected area not more than 3 to 4 times daily. For cough drops, follow the product-specific instructions as per the formulation.

Mechanism of action

Menthol acts as an agonist for the transient receptor potential subtype M8 (TRPM8), a non-selective cation channel that is activated by cold temperatures. This activation leads to calcium influx in mast cells, inducing the release of histamine, which can trigger allergic responses such as urticaria, asthma, and rhinitis. Menthol's ability to induce histamine release via TRPM8 suggests potential therapeutic applications for TRPM8 antagonists in managing cold- and menthol-induced allergies.

Pharmacodynamics

Menthol produces a cooling effect by stimulating sensory neurons that convey cold sensations. It interacts with TRPM8 channels, leading to the activation of intracellular signaling pathways that can result in vasodilation and increased blood flow to the area of application. This cooling sensation can provide symptomatic relief in conditions characterized by pain or irritation.

Pharmacokinetics

Menthol is absorbed through the skin and mucous membranes, with systemic effects depending on the route of administration. Its bioavailability can vary, and it is metabolized primarily in the liver. The elimination half-life and excretion pathways have not been extensively characterized, but menthol is generally considered to have a rapid onset of action with effects lasting for a few hours.

Adverse effects

• Allergic reactions
• Urticaria
• Asthma
• Rhinitis
• Skin irritation

Precautions

• Use with caution in patients with known allergies to menthol or related compounds
• May exacerbate asthma in sensitive individuals

Pregnancy

There are no well-controlled studies of menthol in pregnant women. Menthol should be used during pregnancy only if clearly needed.

Breast-feeding

Menthol is excreted in breast milk. Caution should be exercised when administering to nursing mothers.

Storage

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

Formulations

• Topical ointment
• Cream
• Liquid

Indications

• Allergic conditions
• Autoimmune diseases
• Asthma and chronic obstructive pulmonary disease (COPD)
• Certain cancers (e.g., leukemia, lymphoma)
• Skin conditions (e.g., dermatitis)
• Inflammatory bowel disease
• Multiple sclerosis exacerbations
• Severe infections requiring immunosuppression

Dosage

Children: Refer to BNF for Children for specific dosing; doses vary significantly based on the child's age, weight, and condition being treated.

Adults: Refer to BNF for specific dosing; typically, initial doses range from 4 to 48 mg depending on the severity of the condition.

Mechanism of action

Methylprednisolone exerts its effects by binding to glucocorticoid receptors, leading to the modulation of gene expression. This interaction influences the transcription of anti-inflammatory proteins while suppressing the expression of pro-inflammatory genes, ultimately resulting in reduced inflammation and immune response.

Pharmacodynamics

The pharmacodynamic effects of methylprednisolone are characterized by its ability to decrease inflammation, suppress the immune response, and affect carbohydrate metabolism. Therapeutic doses lead to various systemic effects, including modification of leukocyte distribution and inhibition of cytokine production.

Pharmacokinetics

Methylprednisolone is well absorbed after oral administration, with a bioavailability of approximately 50%. It has a volume of distribution that reflects extensive tissue binding. The drug is metabolized primarily in the liver through conjugation and reduction, and its metabolites are excreted in urine. The half-life varies based on the route of administration but is generally around 18 to 36 hours.

Adverse effects

• Increased blood pressure
• Hyperglycemia
• Weight gain
• Mood changes
• Insomnia
• Gastrointestinal disturbances
• Increased susceptibility to infections

Interactions

• methylphenidate+apraclonidine: Severe (decreases effects)
• methylthioninium chloride+bupropion: Severe (increases risk of severe hypertension)
• methylphenidate+linezolid: Severe (increases risk of elevated blood pressure)
• rasagiline+methylphenidate: Severe (increases risk of a hypertensive crisis)
• mao-inhibitors+methylphenidate: Severe (increases risk of a hypertensive crisis)
• dronedarone+methylprednisolone: Moderate (increases exposure)
• miconazole+methylprednisolone: Moderate (increases concentration)
• antifungals, azoles+methylprednisolone: Moderate (increases exposure)
• crizotinib+methylprednisolone: Moderate (increases exposure)

Precautions

• Use with caution in patients with hypertension
• Monitor blood glucose levels in diabetic patients
• Consider potential for infection risk due to immunosuppression
• Evaluate for psychiatric effects in susceptible individuals

Pregnancy

Corticosteroids may be used during pregnancy if the potential benefit justifies the risk to the fetus. Careful monitoring is advised.

Breast-feeding

Corticosteroids are excreted in breast milk; caution is advised. Monitor the infant for potential effects.

Storage

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

Formulations

• Tablets
• Injectable solutions
• Topical preparations

Mechanism of action

Methylsulphate functions as a methylating agent, transferring a methyl group to nucleophiles. This process involves the formation of a sulfonium ion, which is highly reactive and can readily react with nucleophilic sites on various substrates, leading to methylation reactions.

Pharmacodynamics

The pharmacodynamics of methylsulphate is primarily related to its role as a methylating agent in biochemical reactions. It can alter the structure and function of biological molecules, potentially affecting cellular processes and signaling pathways. However, detailed pharmacodynamic studies specific to therapeutic use are limited.

Pharmacokinetics

There is limited information on the pharmacokinetics of methylsulphate, given its typical use as a reagent in laboratory settings rather than a clinical drug. When used in chemical reactions, its reactivity and transformation into other compounds would dictate its pharmacokinetic profile, which could vary significantly based on the specific context of use.

Pregnancy

There is limited data on the use of methylsulphate in pregnancy. Consult relevant guidelines.

Breast-feeding

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

Storage

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

Indications

• Topical antiseptic for skin disinfection
• Surgical scrubs and hand sanitizers
• Wound care management
• Pharmaceutical excipient in solid and liquid formulations

Dosage

Children: Refer to specific product guidelines for pediatric dosing recommendations, as doses can vary based on formulation and intended use.

Adults: Refer to specific product guidelines for dosing recommendations, as doses can vary based on the formulation and intended use.

Mechanism of action

Povidone acts by forming a complex with iodine when used as an antiseptic, which releases iodine slowly to exert its antimicrobial effect. The iodine disrupts microbial cell walls and interferes with protein synthesis, leading to cell death. Additionally, as a polymer, povidone can enhance drug solubility and stability by forming a hydrophilic matrix.

Pharmacodynamics

Povidone has a broad spectrum of antimicrobial activity against bacteria, viruses, and fungi. Its antiseptic properties are primarily due to the release of iodine, which is effective in reducing microbial load and preventing infection. The polymer's ability to bind to various substances allows it to be utilized in formulations that require improved stability and solubility.

Pharmacokinetics

Povidone is not absorbed systemically when applied topically, as it remains localized at the site of application. Its pharmacokinetics are largely dependent on the formulation and route of administration, with the polymer being metabolized by hydrolysis and excreted in urine as low-molecular-weight compounds. The release and activity of iodine are influenced by the concentration of povidone and the presence of organic matter.

Adverse effects

• Local irritation
• Allergic reactions
• Skin rashes
• Hypersensitivity reactions

Precautions

• Use with caution in patients with known allergies to iodine or povidone-iodine
• Avoid use in deep puncture wounds or serious burns

Pregnancy

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

Breast-feeding

Povidone is considered safe during breastfeeding, but it is recommended to consult a healthcare professional.

Storage

Store at room temperature, away from moisture and heat. Keep the container tightly closed.

Formulations

• Topical solution
• Ointment
• Surgical scrub
• Gauze impregnated with povidone-iodine

Indications

• Management of diabetes
• Weight management
• Sugar substitutes in food and beverages

Dosage

Children: Refer to the BNF for Children for specific dosage information. Caution is advised when using artificial sweeteners in children.

Adults: Refer to the BNF for specific dosage information. Generally, saccharin is used in very small quantities due to its high sweetness intensity.

Mechanism of action

Saccharin activates specific T2R bitter taste receptors, contributing to the perception of sweetness and the bitter aftertaste associated with saccharin and acesulfame-K. Additionally, it has been shown to stimulate transient receptor potential vanilloid-1 (TRPV1) receptors, which are present in taste receptor cells and nerve terminals throughout the oral cavity. The activation of TRPV1 may play a role in the aftertaste or metallic taste sensation often reported with saccharin consumption.

Pharmacodynamics

Due to its high sweetness intensity, saccharin can effectively mimic the taste of sugar without contributing to caloric intake. It alters taste perception by engaging receptors responsible for taste sensation, particularly affecting the sweet and bitter taste pathways. Its effect on TRPV1 receptors suggests a complex interaction that may enhance the sensory experience of sweetness while also causing potential off-tastes.

Pharmacokinetics

Saccharin is not metabolized by the body and is excreted unchanged in the urine. Its absorption occurs in the gastrointestinal tract, but due to its non-nutritive nature, it does not undergo significant metabolic processes. The pharmacokinetic profile indicates that saccharin has a rapid onset of action with a prolonged sweet taste effect, although individual responses may vary.

Adverse effects

• Allergic reactions
• Headaches
• Nausea
• Gastrointestinal disturbances

Precautions

• Use with caution in individuals with a history of hypersensitivity to saccharin or its derivatives
• Avoid excessive consumption to prevent possible adverse effects

Pregnancy

Saccharin is generally not recommended during pregnancy due to potential risks, although human studies have shown no clear evidence of harm.

Breast-feeding

Saccharin is excreted in breast milk; caution is advised when used by nursing mothers.

Storage

Store in a cool, dry place away from light.

Formulations

• Tablets
• Powder

Indications

• Pain relief
• Fever reduction
• Inflammatory conditions such as arthritis
• Prevention of cardiovascular events in certain populations

Dosage

Children: Refer to the BNF for Children for specific dosing guidelines.

Adults: Refer to the BNF for specific dosing guidelines.

Mechanism of action

Salicylate works by inhibiting the enzyme cyclooxygenase (COX), which is involved in the synthesis of prostaglandins. Prostaglandins are lipid compounds that mediate inflammation, pain, and fever. By decreasing the production of these compounds, salicylate effectively reduces inflammation and provides analgesic and antipyretic effects.

Pharmacodynamics

The pharmacodynamic effects of salicylate include analgesia, antipyresis, and anti-inflammatory action. It reduces the sensitivity of pain receptors and inhibits the generation of pain signals. The antipyretic effect is achieved through action on the hypothalamus, leading to peripheral vasodilation and sweating, thereby reducing body temperature. The drug also modulates the immune response, contributing to its anti-inflammatory properties.

Pharmacokinetics

Salicylate is rapidly absorbed from the gastrointestinal tract following oral administration. Peak plasma concentrations are typically reached within 1 to 2 hours. It is extensively metabolized in the liver, primarily through conjugation, and its metabolites are excreted in the urine. The elimination half-life of salicylate varies depending on the dose and the presence of other medications, averaging around 2 to 3 hours at low doses, but can be prolonged at higher doses due to saturation of metabolic pathways.

Contra-indications

• Hypersensitivity to salicylates
• Active peptic ulcer disease
• Severe hepatic impairment
• Severe renal impairment
• Bleeding disorders
• Children with viral infections (due to risk of Reye's syndrome)

Adverse effects

• Gastrointestinal irritation
• Nausea
• Vomiting
• Tinnitus
• Hearing loss
• Allergic reactions
• Rash
• Asthma exacerbation
• Gastric ulceration

Interactions

• Anticoagulants (increased bleeding risk)
• Methotrexate (increased toxicity)
• NSAIDs (increased gastrointestinal side effects)
• Diuretics (reduced efficacy)
• Alcohol (increased risk of gastrointestinal bleeding)

Precautions

• Use with caution in patients with a history of gastrointestinal disease
• Monitor renal function in long-term use
• Caution in patients with asthma or allergies
• Consider alternative therapy in children with viral infections

Pregnancy

Use with caution during pregnancy, particularly in the third trimester, as it may affect fetal development.

Breast-feeding

Salicylate is excreted in breast milk; caution is advised when administering to breastfeeding mothers.

Storage

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

Formulations

• Tablets
• Oral suspension
• Topical preparations
• Suppositories

Mechanism of action

Ethanol affects the brain’s neurons in several ways. It alters their membranes as well as their ion channels, enzymes, and receptors. Alcohol also binds directly to the receptors for acetylcholine, serotonin, GABA, and the NMDA receptors for glutamate. The sedative effects of ethanol are mediated through binding to GABA receptors and glycine receptors (alpha 1 and alpha 2 subunits). It also inhibits NMDA receptor functioning. In its role as an anti-infective, ethanol acts as an osmolyte or dehydrating agent that disrupts the osmotic balance across cell membranes. ... Ethanol is known to affect a large number of membrane proteins that participate in signaling pathways such as neurotransmitter receptors, enzymes, and ion channels, and there is extensive evidence that ethanol interacts with a variety of neurotransmitters. The major actions of ethanol involve enhancing the inhibitory effects of gamma-aminobutyric acid (GABA) at GABAa receptors and blockade of the N-methyl-D-aspartate (NMDA) subtype of glutamate, an excitatory amine acid (EAA) receptor. Animal studies indicate that the acute effects of ethanol result from competitive inhibition of glycine binding to NMDA receptor and disruption of glutamatergic neurotransmission by inhibiting the response of the NMDA receptor. Persistent glycine antagonism and attenuation of glutamatergic neurotransmission by chronic ethanol exposure results in tolerance to ethanol by enhancing EAA neurotransmission and NMDA receptor upregulation. The latter appears to involve selective increases in NMDA R2B subunit concentrations and other molecular changes in specific brain loci. The abrupt withdrawal of ethanol thus produces a hyperexcitable state that leads to the ethanol withdrawal syndrome and excitotoxic neuronal death. GABA-mediated inhibition, which normally acts to limit excitation, is eliminated during ethanol withdrawal syndrome and further intensifies this excitation. In addition, NMDA receptors function to inhibit the release of dopamine in the nucleus accumbens and mesolimbic structures, which modulate the reinforcing action of addictive xenobiotics such as ethanol. By inhibiting NMDA receptor activity, ethanol could increase dopamine release from the nucleus accumbens and ventral tegmental area and could thus create dependence. Chronic ethanol administration also results in tolerance, dependence, and an ethanol withdrawal syndrome, mediated, in part, by desensitization and or downregulation of GABAa receptors. The development of alcoholic ketoacidosis (AKA) requires that a combination of physical and physiologic events occur. The normal response to starvation and depletion of hepatic glycogen stores is for amino acids to be converted to pyruvate. Pyruvate can serve as a substrate for gluconeogenesis, be converted to acetyl-CoA, which can enter the Krebs cycle or can be utilized in various biosynthetic pathways (eg, fatty acid, ketone bodies, cholesterol, and acetylcholine) ... Ethanol metabolism generates NADH, resulting in an excess of reducing potential. This high redox state favors the conversion of pyruvate to lactate, diverting pyruvate from being a substrate for gluconeogenesis. To compensate for the lack of normal metabolic substrates, the body mobilizes fat from adipose tissue and increased fatty acid metabolism as an alternative source of energy. This response is mediated by a decrease in insulin and an increased secretion of glucagon, catecholamines, growth hormone, and cortisol. Fatty acid metabolism results in the formation of acetyl-CoA and it combines with the excess acetate that is generated from ethanol metabolism to form acetoacetate. Most of the acetoacetate is reduced to beta-hydroxybutyrate due to the excess reducing potential or high redox state of the cell. Volume depletion interferes with the renal elimination of acetoacetate and beta-hydroxybutyrate, and contributes to the acidosis. An elevated lactate concentration may result from shunting from pyruvate or

Pharmacodynamics

Alcohol produces injury to cells by dehydration and precipitation of the cytoplasm or protoplasm. This accounts for its bacteriocidal and antifungal action. When alcohol is injected in close proximity to nerve tissues, it produces neuritis and nerve degeneration (neurolysis). Ninety to 98% of ethanol that enters the body is completely oxidized. Ethanol is also used as a cosolvent to dissolve many insoluble drugs and to serve as a mild sedative in some medicinal formulations. Ethanol also binds to GABA, glycine, NMDA receptors and modulates their effects. Ethanol is also metabolised by the hepatic enzyme alcohol dehydrogenase.

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

Molecular iodine is known to inhibit the induction and promotion of N-methyl-n-nitrosourea-induced mammary carcinogenesis, to regress 7,12-dimethylbenz(a)anthracene-induced breast tumors in rats.It has also been shown to have beneficial effects in fibrocystic human breast disease. An acute iodide excess (above the preexisting dietary intake) transiently decreases the production of thyroid hormones in the thyroid gland; this is referred to as the acute Wolff-Chaikoff effect. In normal people, this is followed by a return to normal levels of hormone synthesis, referred to as escape from the acute Wolff-Chaikoff effect, without a significant change in circulating hormone levels. Escape is thought to be the result of down regulation of the sodium-iodide symport (NIS), the iodide transporter in the thyroid gland, resulting in a decrease in the intrathyroidal iodine and the resumption of normal hormone synthesis. An acute or chronic excess of iodide can also decrease circulating T4 and T3 levels and induce a hypothyroid state in some people who have underlying thyroid disorders. These effects are the result of a failure to escape from the acute Wolff-Chaikoff effect. Most people who experience iodine-induced hypothyroidism recover when the excess iodine intake is discontinued.

Mechanism of action

Exposure to low temperatures often causes allergic responses or urticaria. Similarly, menthol, a common food additive is also known to cause urticaria, asthma, and rhinitis. However, despite the obvious clinical implications, the molecular mechanisms responsible for inducing allergic responses to low temperatures and menthol have not been determined. Because a non-selective cation channel, transient receptor potential subtype M8 (TRPM8) is activated by cold and menthol, we hypothesized that this channel mediates cold- and menthol-induced histamine release in mast cells. Here, we report that TRPM8 is expressed in the basophilic leukemia mast cell line, RBL-2H3, and that exposure to menthol or low temperatures induced Ca(2+) influx in RBL-2H3 cells, which was reversed by a TRPM8 blocker. Furthermore, menthol, a TRPM8 agonist, induced the dose-dependent release of histamine from RBL-2H3 cells. When TRPM8 transcripts were reduced by siRNA (small interfering RNA), menthol- and cold-induced Ca(2+) influx and histamine release were significantly reduced. In addition, subcutaneous injection of menthol evoked scratching, a typical histamine-induced response which was reversed by a TRPM8 blocker. Thus, our findings indicate that TRPM8 mediates the menthol- and cold-induced allergic responses of mast cells, and suggest that TRPM8 antagonists be viewed as potential treatments for cold- and menthol-induced allergies. /DL-Menthol/ Menthol's characteristic cooling sensation is due, in part, to the activation of sensory neurons generally termed transient receptor potential (TRP) channels, in particular transient receptor potential melastatin family member 8 (TRPM8) and transient receptor potential subfamily A, member 1 (TRPA1). Menthol acts upon TRPM8 receptors by rapidly increasing intracellular calcium and mobilizing calcium flux through the channels to induce cold response signals at the application site. Aside from its cold-inducing sensation capabilities, menthol exhibits cytotoxic effects in cancer cells, induces reduction in malignant cell growth, and engages in synergistic excitation of GABA receptors and sodium ion channels resulting in analgesia. /DL-Menthol/ In recent years, the transient receptor potential melastatin member 8 (TRPM8) channel has emerged as a promising prognostic marker and putative therapeutic target in prostate cancer. We have found that forced overexpression of TRPM8 in PC-3 cells can inhibit the cell proliferation and motility probably through the TRPM8 activation. In this study, we aimed to investigate whether activating the TRPM8 channel by its selective agonist menthol can inhibit the proliferation and motility of androgen-independent prostate cancer (AIPC) with remarkable expression of TRPM8. Menthol is a naturally occurring compound, which has been widely used in cosmetics and pharmaceutical products, and also as flavoring in food. DU145 cells are androgen-independent but have a remarkable expression of TRPM8. The demonstration of the existence of TRPM8 and the absence of TRPA1 in DU145 cells provided the foundation for the following experiments, because both TRPM8 and TRPA1 are molecular targets of menthol. The outcome of MTT assay indicated that menthol inhibited the cell growth (p < 0.01). Cell cycle distribution and scratch assay analysis revealed that menthol induced cell cycle arrest at the G(0)/G(1) phase (p < 0.01). Furthermore, menthol inhibited the migration of DU145 cells by downregulating the focal-adhesion kinase. So it suggests that the activation of the existing TRPM8 channels may serve as a potential and pragmatic treatment for those AIPC with remarkable expression of TRPM8, and menthol is a useful compound for future development as an anticancer agent. /DL-Menthol/

Mechanism of action

...it has been shown that the activation of particular T2R bitter taste receptors is partially involved with the bitter aftertaste sensation of saccharin and acesulfame-K. ... /This study/ addressed the question of whether /they/ could stimulate transient receptor potential vanilloid-1 (TRPV1) receptors, as these receptors are activated by a large range of structurally different chemicals. Moreover, TRPV1 receptors and/or their variants are found in taste receptor cells and in nerve terminals throughout the oral cavity. Hence, TRPV1 activation could be involved in the ... aftertaste or even contribute to the poorly understood metallic taste sensation. Using Ca(2+) imaging on TRPV1 receptors heterologously expressed in the human embryonic kidney (HEK) 293 cells and on dissociated primary sensory neurons,... /it was found/ that in both systems, .../sweeteners/ activate TRPV1 receptors, and, moreover, they sensitize these channels to acid and heat. ... /it was/also found that TRPV1 receptors were activated by CuSO(4), ZnSO(4), and FeSO(4), three salts known to produce a metallic taste sensation. In summary, .../the/ results identify a novel group of compounds that activate TRPV1 and, consequently, provide a molecular mechanism that may account for off tastes of sweeteners and metallic tasting salts.