NCP LIQUID ANTISEPTIC

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

• General anesthesia for surgical procedures
• Induction and maintenance of anesthesia
• Maintenance of anesthesia in outpatient surgery

Dosage

Children: Dosage for pediatric patients should be determined based on age, weight, and clinical condition. Refer to pediatric anesthesia guidelines for specific dosing recommendations.

Adults: Dosage is individualized based on the patient's condition, the surgical procedure, and the specific agent used. Refer to specific guidelines for each halogenated agent.

Mechanism of action

Halogenated anesthetics primarily work by enhancing the inhibitory neurotransmission mediated by gamma-aminobutyric acid (GABA) at GABA_A receptors in the central nervous system. They also inhibit excitatory neurotransmission by blocking the N-methyl-D-aspartate (NMDA) receptor. This dual action leads to a decrease in neuronal excitability, resulting in sedation and loss of consciousness.

Pharmacodynamics

The pharmacodynamics of halogenated anesthetics involve their effects on the central nervous system, leading to sedation, analgesia, and muscle relaxation. The potency of these agents is often measured by the minimum alveolar concentration (MAC), which is the concentration required to prevent movement in response to surgical stimuli in 50% of patients. Halogenated anesthetics also affect cardiovascular and respiratory systems, potentially causing dose-dependent hypotension and respiratory depression.

Pharmacokinetics

Halogenated anesthetics are typically administered via inhalation and are rapidly absorbed into the bloodstream through the alveoli of the lungs. They are distributed throughout the body, including the brain, where they exert their anesthetic effects. Their elimination occurs primarily through exhalation, although some metabolism may occur in the liver. The onset and duration of action can vary significantly among different halogenated agents, influenced by their solubility in blood and tissues.

Pregnancy

Halogenated compounds should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Consultation with a healthcare provider is recommended.

Breast-feeding

Caution is advised when administering halogenated compounds during breastfeeding, as these substances may pass into breast milk.

Storage

Halogenated compounds should be stored in a cool, dry place, away from light and heat sources. Specific storage conditions may vary based on the individual compound.

Indications

• Antiseptic use in wounds
• Pain relief in inflammatory conditions
• Treatment of infections caused by bacteria and fungi
• Antioxidant therapy
• Management of skin disorders

Dosage

Children: Pediatric dosing should be determined based on specific phenolic compounds and indications, consulting relevant pediatric guidelines or references.

Adults: Dosage varies widely depending on the specific phenolic compound and its intended use. Refer to specific product guidelines for dosing information.

Mechanism of action

Phenols exert their pharmacological effects primarily through their ability to denature proteins and disrupt cell membranes, leading to bactericidal and fungicidal activity. They can also modulate enzyme activity due to their ability to form covalent bonds with amino acid residues in proteins, particularly cysteine residues, affecting various metabolic pathways.

Pharmacodynamics

The pharmacodynamic profile of phenols is characterized by their antiseptic, analgesic, and anti-inflammatory properties. They can inhibit the growth of bacteria, fungi, and viruses through their cytotoxic effects. Additionally, phenolic compounds can scavenge free radicals, reducing oxidative stress and inflammation in tissues, which contributes to their therapeutic effects in pain and inflammation management.

Pharmacokinetics

Phenols are generally well absorbed through the skin and gastrointestinal tract, though their bioavailability can vary based on the specific compound. They are metabolized primarily in the liver through conjugation and oxidation pathways, forming various metabolites that may also exhibit biological activity. Elimination occurs mainly via renal excretion, with the rate influenced by the specific phenolic compound and its formulation.

Adverse effects

• Skin irritation
• Respiratory distress
• Nausea
• Vomiting
• Headache
• Dizziness
• Cough
• Burning sensation

Precautions

• Use with caution in patients with respiratory conditions
• Avoid contact with skin and mucous membranes
• Monitor for signs of toxicity in high doses

Pregnancy

Safety in pregnancy has not been established. Use only if clearly needed.

Breast-feeding

Caution is advised as it may be excreted in breast milk.

Storage

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

Formulations

• Topical solutions
• Ointments
• Liquid preparations
• Tablets

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

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.