TETRANOR 10%

Indications

• Bacterial infections (e.g. Chlamydia, Rickettsia, Mycoplasma)
• Acne
• Prophylaxis of asymptomatic meningococcal carrier state (not recommended)

Dosage

Adults: For adult patients, the typical dosage of oxytetracycline for susceptible infections is 100 mg twice daily for 5 days. For other conditions, such as acne, the dosage may be 500 mg twice daily, usually for a duration of 6 to 12 weeks, with the possibility of repeating the course intermittently.

Mechanism of action

Oxytetracycline exerts its antibacterial effects by binding to the 30S ribosomal subunit of bacteria, inhibiting the binding of aminoacyl-tRNA to the mRNA-ribosome complex. This action prevents the synthesis of proteins essential for bacterial growth and replication, leading to the bacteriostatic effect of the drug.

Pharmacodynamics

The pharmacodynamics of oxytetracycline involve its ability to inhibit bacterial protein synthesis, which is critical for the growth and reproduction of bacteria. The drug demonstrates a broad spectrum of activity against both Gram-positive and Gram-negative organisms, as well as some atypical pathogens. Its effectiveness can be influenced by the presence of tetracycline resistance mechanisms in certain bacterial strains.

Pharmacokinetics

Oxytetracycline is well absorbed from the gastrointestinal tract, with peak plasma concentrations occurring approximately 1-2 hours after oral administration. It has a relatively long half-life of about 8-10 hours, allowing for twice-daily dosing. The drug is widely distributed in body tissues and fluids, including the liver, kidneys, and lungs, but is less effective in central nervous system infections due to limited penetration. It is primarily excreted via urine, and dosage adjustments may be necessary in patients with renal impairment.

Contra-indications

• Children under 12 years due to deposition in growing bone and teeth, causing staining and occasionally dental hypoplasia

Adverse effects

• Gastrointestinal disturbances
• Photosensitivity
• Dental discoloration
• Hepatotoxicity
• Renal impairment
• Skin reactions including rash and urticaria
• Ataxia
• Hearing impairment
• Colitis
• Systemic lupus erythematosus exacerbation

Interactions

• Antacids and supplements containing calcium, magnesium, or iron may reduce absorption
• Oral contraceptives may be less effective
• Other tetracyclines
• Warfarin (may increase anticoagulant effect)

Precautions

• Use with caution in patients with renal impairment
• Monitor for hepatic toxicity in long-term use
• Patients should be advised to avoid excessive sunlight exposure
• Discontinue if systemic lupus erythematosus develops or worsens

Pregnancy

Oxytetracycline is contraindicated during pregnancy due to potential harm to fetal development, particularly affecting bone and dental health.

Breast-feeding

Use with caution; oxytetracycline is excreted in breast milk and may affect the infant's dental health.

Storage

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

Formulations

• Oxytetracycline 250 mg tablets
• Oxytetracycline oral suspension
• Oxytetracycline oral solution

Indications

• Warts
• Plantar warts
• Verrucas
• Umbilical granulomas

Dosage

Children: Apply twice daily for up to 3 consecutive days. Treatment may be repeated at weekly intervals if necessary for a total of four 3-day treatment courses, under specialist supervision.

Adults: Apply twice daily to the lesion for a maximum of 3 applications. Instructions generally recommend removing dead skin before use by gentle filing and covering with an adhesive dressing after application.

Mechanism of action

Formaldehyde is thought to act via sensory nerve fibers that signal through the trigeminal nerve, reflexively inducing bronchoconstriction through the vagus nerve. It may also disrupt miRNA expression levels within lung cells, representing a novel epigenetic mechanism through which formaldehyde may induce disease. Exposure to formaldehyde has been linked to alterations in gene expression that can contribute to diseases, particularly affecting the respiratory system.

Pharmacodynamics

Formaldehyde exhibits irritant properties, particularly affecting mucosal membranes and respiratory tissues. Its action leads to bronchoconstriction and inflammation upon exposure, indicating significant pharmacological activity as a respiratory irritant. Its potential to induce cellular changes and dysregulation of miRNA expression points to broader implications in disease pathology, particularly in lung tissue.

Pharmacokinetics

Formaldehyde is rapidly absorbed through inhalation and is metabolized primarily in the liver to form formic acid. Its short half-life and high reactivity limit its systemic exposure. The compound is known to form various adducts with proteins and DNA, contributing to its toxicological profile. Excretion is primarily via urine, as formic acid, with minimal excretion of unchanged formaldehyde.

Contra-indications

• Not for application to broken skin
• Not for application to anogenital areas
• Not for application to the face or mucosa

Adverse effects

• Skin irritation
• Rash
• Severe cutaneous adverse reactions
• Methhaemoglobinaemia
• Argyria

Precautions

• Avoid contact with normal skin and open wounds
• Protect surrounding skin with soft paraffin
• May be very irritant to eyes

Pregnancy

Avoid use during pregnancy due to potential harmful effects.

Breast-feeding

Avoid use during breastfeeding due to potential harmful effects.

Storage

Store in a cool, dry place away from light.

Formulations

• Formaldehyde solution 4% (Buffered)
• Formaldehyde liquid 10%

Indications

• Phospholipid biosynthesis disorders
• Neurotransmitter synthesis-related conditions
• Potential use in lipid metabolism abnormalities

Dosage

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

Adults: Refer to the BNF for specific dosing information.

Mechanism of action

Ethanolamine serves as a precursor in the biosynthesis of phospholipids, particularly phosphatidylethanolamine and phosphatidylcholine, which are critical for maintaining cell membrane integrity and functionality. It participates in various metabolic pathways that convert it into other bioactive molecules.

Pharmacodynamics

Ethanolamine's pharmacodynamic properties are largely attributed to its role in phospholipid metabolism. By contributing to the structural integrity of cell membranes, it influences cellular signaling and membrane fluidity, which can affect various physiological responses. Its involvement in neurotransmitter synthesis may also suggest a role in modulating neuronal activity.

Pharmacokinetics

The pharmacokinetics of ethanolamine are not extensively characterized; however, it is generally absorbed when administered and metabolized in the liver. Its metabolites are likely excreted via the kidneys. Specific data regarding half-life, volume of distribution, and clearance are not well-documented.

Pregnancy

Ethanolamine should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

It is not known whether ethanolamine is excreted in human milk. Caution should be exercised when administering to breastfeeding women.

Storage

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

Formulations

• Ethanolamine solution

Indications

• Industrial solvent
• Chemical reaction medium
• Pharmaceutical formulation aid

Mechanism of action

N-methylpyrrolidone acts primarily as a polar aprotic solvent. It can solvate both polar and non-polar compounds, facilitating reactions and processes by enhancing the solubility of various substances. NMP does not ionize in solution, which allows it to stabilize intermediates during chemical reactions.

Pharmacodynamics

In pharmacodynamics, N-methylpyrrolidone exhibits properties that enhance the permeability of biological membranes, which can aid in the absorption of certain drugs. Its solvent characteristics support the dissolution and transportation of various pharmacological agents.

Pharmacokinetics

N-methylpyrrolidone is absorbed through the skin and mucous membranes, with a relatively low bioaccumulation potential. It is metabolized primarily in the liver, with metabolites excreted in urine. The half-life and specific metabolic pathways are not well defined, but it is known to undergo conjugation and oxidation processes.

Pregnancy

There is limited data on the use of N-methylpyrrolidone in pregnant women. It is advisable to avoid use during pregnancy unless the potential benefits justify the risks.

Breast-feeding

There is insufficient information regarding the excretion of N-methylpyrrolidone in human milk. Caution should be exercised when administering to breastfeeding women.

Storage

Store in a well-closed container at room temperature, away from light and moisture.

Mechanism of action

Oxides do not have a single mechanism of action as they are a broad category of compounds. However, in general, metal oxides can exhibit catalytic properties, while non-metal oxides may participate in biochemical reactions by forming acids or bases upon dissolution in water.

Pharmacodynamics

The pharmacodynamics of oxides depend on the specific type of oxide and its interaction with biological systems. For instance, metal oxides may have antimicrobial properties, while certain non-metal oxides can influence metabolic pathways through their acid-base chemistry. The effects vary widely, necessitating specific studies for each oxide's role in therapeutic contexts.

Pharmacokinetics

The pharmacokinetics of oxides are also variable. Many metal oxides are poorly soluble and thus have limited absorption when ingested. Non-metal oxides, such as carbon dioxide, can be readily absorbed and utilized in metabolic processes. The distribution, metabolism, and excretion of oxides depend on their chemical form and the biological system in which they are involved.

Pregnancy

Not applicable as oxide is not a drug but a class of chemical compounds.

Breast-feeding

Not applicable as oxide is not a drug but a class of chemical compounds.

Storage

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

Indications

• Mood disorders
• Anxiety disorders
• Neurotransmitter modulation

Dosage

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

Adults: Refer to the BNF for specific dosing guidance as it may vary based on the condition being treated.

Mechanism of action

Sulfoxylate acts as a modulator of neurotransmitter systems, specifically influencing the activity of monoamines such as serotonin and norepinephrine. It may exert its effects by altering synaptic transmission and enhancing the release of these neurotransmitters, contributing to its therapeutic effects in mood and anxiety disorders.

Pharmacodynamics

The pharmacodynamics of sulfoxylate involve its interaction with receptors and transporters in the central nervous system. By enhancing neurotransmitter availability, it can lead to improved mood and anxiety levels. The precise dose-response relationship and the time course of its effects may vary among individuals, necessitating careful monitoring in clinical use.

Pharmacokinetics

The pharmacokinetics of sulfoxylate are not extensively characterized in the available literature. However, it is expected to be absorbed following administration, with distribution occurring throughout the body, particularly in tissues rich in serotonin and norepinephrine receptors. Metabolism and excretion pathways remain to be fully elucidated, and further studies are required to clarify these aspects.

Pregnancy

Consult with a healthcare professional before use. Limited data available on safety during pregnancy.

Breast-feeding

Consult with a healthcare professional before use. Limited data available on safety during breastfeeding.

Storage

Store in a cool, dry place away from light.

Mechanism of action

Formaldehyde is thought to act via sensory nerve fibers that signal through the trigeminal nerve to reflexively induce bronchoconstriction through the vagus nerve. Exposure to formaldehyde, a known air toxic, is associated with cancer and lung disease. Despite the adverse health effects of formaldehyde, the mechanisms underlying formaldehyde-induced disease remain largely unknown. Research has uncovered microRNAs (miRNAs) as key posttranscriptional regulators of gene expression that may influence cellular disease state. Although studies have compared different miRNA expression patterns between diseased and healthy tissue, this is the first study to examine perturbations in global miRNA levels resulting from formaldehyde exposure. We investigated whether cellular miRNA expression profiles are modified by formaldehyde exposure to test the hypothesis that formaldehyde exposure disrupts miRNA expression levels within lung cells, representing a novel epigenetic mechanism through which formaldehyde may induce disease. Human lung epithelial cells were grown at air-liquid interface and exposed to gaseous formaldehyde at 1 ppm for 4 hr. Small RNAs and protein were collected and analyzed for miRNA expression using microarray analysis and for interleukin (IL-8) protein levels by enzyme-linked immunosorbent assay (ELISA). RESULTS: Gaseous formaldehyde exposure altered the miRNA expression profiles in human lung cells. Specifically, 89 miRNAs were significantly down-regulated in formaldehyde-exposed samples versus controls. Functional and molecular network analysis of the predicted miRNA transcript targets revealed that formaldehyde exposure potentially alters signaling pathways associated with cancer, inflammatory response, and endocrine system regulation. IL-8 release increased in cells exposed to formaldehyde, and results were confirmed by real-time polymerase chain reaction. Formaldehyde alters miRNA patterns that regulate gene expression, potentially leading to the initiation of a variety of diseases. Formaldehyde at high concentrations is a contributor to air pollution. It is also an endogenous metabolic product in cells, and when beyond physiological concentrations, has pathological effects on neurons. Formaldehyde induces mis-folding and aggregation of neuronal tau protein, hippocampal neuronal apoptosis, cognitive impairment and loss of memory functions, as well as excitation of peripheral nociceptive neurons in cancer pain models. Intracellular calcium ([Ca(2+)](i)) is an important intracellular messenger, and plays a key role in many pathological processes. The present study aimed to investigate the effect of formaldehyde on [Ca(2+)](i) and the possible involvement of N-methyl-D-aspartate receptors (NMDARs) and T-type Ca(2+) channels on the cell membrane. METHODS: Using primary cultured hippocampal neurons as a model, changes of [Ca(2+)](i) in the presence of formaldehyde at a low concentration were detected by confocal laser scanning microscopy. Formaldehyde at 1 mmol/L approximately doubled [Ca(2+)](i). (2R)-amino-5-phosphonopentanoate (AP5, 25 umol/L, an NMDAR antagonist) and mibefradil (MIB, 1 umol/L, a T-type Ca(2+) channel blocker), given 5 min after formaldehyde perfusion, each partly inhibited the formaldehyde-induced increase of [Ca(2+)](i), and this inhibitory effect was reinforced by combined application of AP5 and MIB. When applied 3 min before formaldehyde perfusion, AP5 (even at 50 umol/L) did not inhibit the formaldehyde-induced increase of [Ca(2+)](i), but MIB (1 umol/L) significantly inhibited this increase by 70%. These results suggest that formaldehyde at a low concentration increases [Ca(2+)](i) in cultured hippocampal neurons; NMDARs and T-type Ca(2+) channels may be involved in this process. /The purpose of this study was/ to study the role of poly (ADP-ribose) polymerase-l (PARP-1) in formaldehyde-induced DNA damage response in human bronchial epithelial (HBE) cells and to investigate the mechanism of