SEMALOG

Indications

• Type 2 diabetes mellitus
• Weight management in patients with obesity
• Cardiovascular risk reduction in patients with diabetes

Dosage

Adults: Initially 3 mg once daily for 1 month, then increased to 7 mg once daily for at least 1 month, and may be further increased to 14 mg once daily if necessary. Take on an empty stomach.

Mechanism of action

Semaglutide is a GLP-1 analog that binds selectively to the GLP-1 receptor, promoting insulin secretion from pancreatic islet cells in a glucose-dependent manner, slowing gastric emptying, and reducing postprandial glucagon secretion. This multi-faceted approach aids in maintaining glucose homeostasis and offers additional benefits in cardiovascular health and weight management.

Pharmacodynamics

Semaglutide has been shown to significantly reduce HbA1c levels, fasting and postprandial glucose levels, systolic blood pressure, and body weight. It also lowers fasting triglycerides and VLDL cholesterol, contributing positively to cardiovascular health. However, it carries risks of medullary thyroid cell carcinoma and pancreatitis, necessitating caution in patients with certain medical histories.

Pharmacokinetics

Semaglutide exhibits high variability in pharmacokinetics, with a peak plasma concentration typically occurring a few hours after administration. It has a long half-life, allowing for once-daily dosing in oral formulation and once-weekly dosing in injectables. The absorption can be affected by gastric emptying, so monitoring for interaction with other drugs is necessary.

Contra-indications

• Diabetic ketoacidosis
• Personal or family history of medullary thyroid carcinoma
• History of pancreatitis
• Severe congestive heart failure

Adverse effects

• Nausea
• Vomiting
• Diarrhea
• Constipation
• Abdominal pain
• Dehydration
• Hypoglycemia
• Pancreatitis
• Weight loss
• Medullary thyroid cell carcinoma (in rodents)

Interactions

• Concomitant insulin or sulfonylureas may require dose adjustments
• Caution with other oral medications due to delayed gastric emptying

Precautions

• Monitor for symptoms of acute pancreatitis (severe abdominal pain)
• Patients must maintain adequate hydration
• Careful blood glucose self-monitoring when initiating therapy

Pregnancy

Avoid - toxicity in animal studies.

Breast-feeding

Avoid - no information available.

Storage

Store in a cool, dry place, protected from light. Follow specific storage instructions provided by the manufacturer.

Formulations

• Oral tablets (3 mg, 7 mg, 14 mg)
• Subcutaneous injection (solution for injection in pre-filled pens)

Indications

• Rectal and anal disorders
• Haemorrhoids
• Pruritus ani

Dosage

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

Adults: For rectal use using aerosol spray: 1 spray up to 3 times a day for no longer than 7 days without medical advice. For ointment: apply several times daily, for short-term use only.

Mechanism of action

Phenol exerts its effects by acting as a potent proteolytic agent. At concentrations of 5% to 7%, it can dissolve tissue through proteolysis. When injected near a nerve, it produces chemical neurolysis, affecting nerve fibers nonselectively. Local anesthetic effects are typically observed within 5 to 10 minutes of application.

Pharmacodynamics

Phenol's pharmacodynamic properties include its ability to cause tissue dissolution and local anesthesia. The local anesthetic effects result from its action on the nerve fibers, leading to a temporary loss of sensation in the affected area. The proteolytic action can assist in the treatment of various skin and mucosal conditions by facilitating tissue breakdown.

Pharmacokinetics

Phenol is absorbed through mucosal surfaces when applied locally. Its metabolism involves biological oxidation and phase I functionalization, primarily through cytochrome P450 enzymes. The elimination of phenol occurs through metabolic pathways, and it can be detected in urine as a result of its metabolism.

Contra-indications

• Infection
• Known hypersensitivity to phenol or its components

Adverse effects

• Local irritation
• Burning sensation
• Paraesthesia
• Vision disorders
• Skin reactions
• Adrenal suppression

Interactions

• Caution with other local anesthetics due to potential additive effects

Precautions

• Use for short periods only-no longer than a few days
• Avoid excessive application, especially on sensitive areas
• Consult product literature for specific guidelines

Pregnancy

Data on the use of phenol during pregnancy is limited; caution is advised.

Breast-feeding

Limited information available; caution is recommended when used in breastfeeding mothers.

Storage

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

Formulations

• Ointment
• Suppository
• Aerosol spray

Indications

• Electrolyte replacement
• Volume expansion in hypovolemic patients
• Management of hyponatremia
• Support in intravenous fluid therapy

Dosage

Children: Refer to the BNF for Children for appropriate dosing in paediatric patients, as dosages may vary based on the formulation and clinical condition.

Adults: Refer to specific product information or clinical guidelines for dosage recommendations, as disodium is often part of combination products.

Mechanism of action

Disodium compounds often function by providing sodium ions that are essential for various physiological processes. Sodium ions play a critical role in maintaining osmotic balance, nerve impulse transmission, and muscle contraction. In the context of intravenous solutions, disodium helps to restore electrolyte balance in patients.

Pharmacodynamics

The pharmacodynamics of disodium is primarily related to its role in electrolyte balance and fluid homeostasis. Sodium ions are vital for the function of excitable tissues, including neurons and muscle cells. Changes in sodium levels can affect blood pressure, hydration status, and overall cellular function.

Pharmacokinetics

The pharmacokinetics of disodium compounds depend on their specific formulation and route of administration. When administered intravenously, disodium is rapidly distributed in the extracellular fluid, where it helps to maintain osmotic pressure. Sodium is primarily excreted by the kidneys, and its levels can be influenced by fluid intake, dietary sodium, and renal function.

Pregnancy

Use with caution. Consult a healthcare provider for specific guidance.

Breast-feeding

Use with caution. Consult a healthcare provider for specific guidance.

Storage

Store at room temperature, away from moisture and direct sunlight.

Dosage

Children: Refer to the BNF for Children for appropriate dosing information in paediatric cases, especially in instances of overdose.

Adults: Refer to the BNF for specific dosing information based on clinical circumstances, particularly in cases of overdose.

Mechanism of action

Ethylene glycol is metabolized by alcohol dehydrogenase to glycoaldehyde, which is subsequently converted to glycolic, glyoxylic, and oxalic acids. These metabolites contribute to anion gap metabolic acidosis and are responsible for tissue injury through the formation of insoluble calcium oxalate crystals.

Pharmacodynamics

The toxicity of ethylene glycol arises from its metabolites, particularly glycolic and oxalic acids. These compounds induce metabolic acidosis, lead to renal failure through calcium oxalate crystal deposition in the kidneys, and can cause neurological impairment. The anion gap increases due to the accumulation of these acids, leading to complications such as cardiovascular instability and potential multi-organ failure.

Pharmacokinetics

Ethylene glycol is rapidly absorbed after oral ingestion. It undergoes first-pass metabolism primarily in the liver, where it is converted into its toxic metabolites. The elimination half-life of ethylene glycol varies but is generally prolonged in cases of renal impairment. Renal excretion of metabolites contributes to the duration of toxicity, necessitating prompt medical intervention in cases of overdose.

Adverse effects

• Metabolic acidosis
• Renal failure
• CNS depression
• Hypocalcemia
• Cardiovascular collapse
• Pulmonary edema

Precautions

• Use with caution in patients with renal impairment
• Monitor for signs of metabolic acidosis
• Evaluate electrolyte levels, particularly calcium

Pregnancy

There is limited data on the safety of ethylene glycol in pregnancy. It should only be used if clearly needed.

Breast-feeding

It is unknown if ethylene glycol is excreted in human milk. Caution is advised.

Storage

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

Formulations

• Liquid

Indications

• Adjustment of pH in pharmaceutical formulations
• Facilitation of drug absorption
• Used in sterile preparations

Dosage

Children: Refer to specific product guidelines for dosing information, as hydrochloric acid is typically used in a controlled setting based on formulation requirements.

Adults: Refer to specific product guidelines for dosing information, as hydrochloric acid is typically used in a controlled setting based on formulation requirements.

Mechanism of action

Hydrochloric acid dissociates in aqueous solution to release hydrogen ions (H+), leading to a decrease in pH. This acidic environment promotes the activation of pepsinogen to pepsin, an enzyme essential for protein digestion. Additionally, the acidity aids in the absorption of certain minerals and drugs that require an acidic environment for optimal bioavailability.

Pharmacodynamics

The primary pharmacodynamic action of hydrochloric acid is the maintenance of gastric acidity, which is essential for normal digestive processes. The acidic environment helps in denaturing proteins, activating digestive enzymes, and providing a barrier against pathogenic microorganisms. Its effects can influence the absorption and efficacy of various medications, particularly those that are pH-dependent.

Pharmacokinetics

Hydrochloric acid does not undergo significant systemic absorption when used in its normal contexts, as it acts locally within the gastrointestinal tract. The amount of hydrochloric acid produced by the stomach varies with food intake and physiological needs. It is secreted by parietal cells in the gastric mucosa, and its secretion is regulated by neural, hormonal, and local factors. The half-life of hydrochloric acid is not applicable as it is continuously produced and neutralized within the gastrointestinal tract.

Contra-indications

• Hypersensitivity to hydrochloric acid or any of its components
• Severe renal impairment
• Active gastrointestinal bleeding

Adverse effects

• Abdominal pain
• Diarrhea
• Nausea
• Vomiting
• Esophageal irritation
• Gastric mucosal irritation
• Electrolyte imbalances

Interactions

• May interact with alkaline substances, potentially neutralizing hydrochloric acid
• Caution with antacids as they may affect the efficacy of hydrochloric acid

Precautions

• Use with caution in patients with a history of gastritis or gastric ulcers
• Monitor electrolytes in prolonged use
• Use cautiously in patients with respiratory conditions due to potential aspiration risks

Pregnancy

Hydrochloric acid is classified as a category C drug. Use during pregnancy only if clearly needed and the potential benefits justify the risks to the fetus.

Breast-feeding

There is limited data on the excretion of hydrochloric acid in human milk. Use with caution during breastfeeding.

Storage

Store in a cool, dry place away from direct sunlight and heat. Ensure the container is tightly closed.

Formulations

• Oral solutions
• Injectable forms
• Tablets

Dosage

Children: Refer to specific guidelines for pediatric dosing; consult the BNF for Children for accurate dosage information.

Adults: Refer to specific guidelines for use; dosage may vary based on the context of use.

Mechanism of action

Hydroxide ions act primarily as bases, neutralizing acids to form water and salts. They participate in various biochemical pathways, including selenium metabolism and the degradation of reactive oxygen species. Hydroxide can influence enzyme activity and stability by altering the pH of the environment, thereby affecting metabolic reactions.

Pharmacodynamics

Hydroxide ions can impact biological processes by changing the local pH, which influences enzyme activity, ion transport, and the solubility of other compounds. Their ability to neutralize acids can help regulate physiological pH, contributing to homeostasis in living organisms.

Pharmacokinetics

As an inorganic ion, hydroxide does not undergo traditional pharmacokinetic processes like absorption, distribution, metabolism, or excretion. Instead, it is rapidly equilibrated in biological fluids and participates in acid-base reactions, having immediate effects on the local environment.

Pregnancy

There is limited information regarding the use of hydroxide during pregnancy. Consult a healthcare professional for advice.

Breast-feeding

Limited data is available on the excretion of hydroxide in breast milk. Consult a healthcare professional before use.

Storage

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

Indications

• Plant growth regulation
• Agricultural applications as a growth inhibitor

Dosage

Children: Not applicable.

Adults: Refer to the relevant agricultural guidelines for specific applications.

Mechanism of action

In an in vitro study, propylene acts as a plant growth inhibitor by inhibiting the oxidation of indole-3-acetic acid by peroxidase in the presence of superoxide anion radicals. This inhibition is linked to the activation of an iron complex (compound III) shuttle, which enhances the reaction rate between superoxide and peroxidase, ultimately affecting plant growth processes. Propylene is a less effective inhibitor compared to ethylene.

Pharmacodynamics

The pharmacodynamic effects of propylene are primarily observed in its role as a growth inhibitor in plants. By modulating the oxidation of phytohormones like indole-3-acetic acid, propylene can influence various growth responses in plants, potentially affecting processes such as cell elongation and division.

Pharmacokinetics

Information on the pharmacokinetics of propylene in humans is not well-documented, as its primary uses are industrial and agricultural. Its metabolism may be influenced by environmental factors, and its effects are primarily studied in the context of plant biology rather than human pharmacology.

Mechanism of action

Phenol is a potent proteolytic agent. Concentrations in the 5% to 7% range dissolve tissue on contact via proteolysis. In high concentrations when injected next to a nerve, phenol produces a chemical neurolysis which is nonselective across nerve fiber size and most prominent on its outer aspect. Local anesthetic effects occur within 5-10 minutes. The effects of monoamine depletors and monoamine denervators on phenol induced tremor were studied in mice. The tremor induced by phenol was enhanced by pretreatment with reserpine or tetrabenazine, but not with syrosingopine. However, alpha-methyl-p-tyrosine, p-chlorophenylalanine or 6-hydroxydopamine did not affect the tremor. These results suggest that the depletion of central monoamines as a whole contribute to the enhancement of the tremor induced by phenol.

Mechanism of action

**Mechanism of glycemic control** GLP-1 is a physiological hormone that promotes glycemic control via several different mechanisms, including insulin secretion, slowing gastric emptying, and reducing postprandial glucagon secretion. The homeostasis of glucose is dependent on hormones such as insulin and amylin, which are secreted by the beta cells of the pancreas. Semaglutide is 94% similar to human GLP-1. Analogs of this hormone such as semaglutide stimulate the synthesis of insulin by stimulating pancreatic islet cells and reducing glucagon secretion. They directly bind with selectivity to the GLP-1 receptor, causing various beneficial downstream effects that reduce blood glucose in a glucose-dependent fashion. **Mechanism of cardiovascular benefit and weight loss** In hypercholesterolemia, semaglutide is believed to reduce the progression of atherosclerosis via decreased gut permeability and decreased inflammation. Weight loss is believed to occur via the reduction of appetite and food cravings after semaglutide administration.

Pharmacodynamics

Semaglutide reduces HbA1c, systolic blood pressure, and body weight. After 12 weeks of treatment, semaglutide decreased fasting and postprandial glucose by increasing insulin production and decreasing glucagon secretion (which is normally associated with increases in blood sugar). Semaglutide also lowers fasting triglycerides and VLDL cholesterol, exerting beneficial effects on cardiovascular health. Semaglutide has been shown to cause medullary thyroid cell carcinoma in rodents. While its clinical relevance to humans is unknown, the FDA advises not to administer this drug in those with a personal or family history of medullary thyroid carcinoma. Semaglutide also poses a risk of pancreatitis and dehydration. Patients must be adequately hydrated while on semaglutide and are advised to seek medical attention immediately in cases of abdominal pain radiating to the back. Because this drug delays gastric emptying, it is important to monitor for the efficacy or adverse effects of other drugs that are administered orally.

Mechanism of action

Ethylene glycol is metabolized by alcohol dehydrogenase to glycoaldehyde, which is then metabolized to glycolic, glyoxylic, and oxalic acids. These acids, along with excess lactic acid are responsible for the anion gap metabolic acidosis. Oxalic acid readily precipitates with calcium to form insoluble calcium oxalate crystals. Tissue injury is caused by widespread deposition of oxalate crystals and the toxic effects of glycolic and glyoxylic acids.

Mechanism of action

In an in vitro study of the mechanism of action of ethylene as a plant growth inhibitor, the effects of ethylene and some of its analogs, including propylene, on the oxidation of indole-3-acetic acid were examined. Ethylene and its analogs inhibited the oxidation of indole-3-acetic acid by peroxidase under conditions where the iron complex (compound III, an oxy-ferrous complex of peroxidase) shuttle was activated. Inhibition occurred only in the presence of the superoxide anion radical 02(-). Spectral and kinetic data indicated that ethylene and its analogs enhanced the rate of reaction of 02(-) with peroxidase; ie, the iron complex (compound III) shuttle, resulting in the formation of compound III. Propylene was a less effective inhibitor than ethylene.