NOSIL 0.05%

Indications

• Nasopharyngitis (common cold)
• Sinusitis (acute)
• Nasal congestion

Dosage

Children: For children aged 12-17 years, the recommended dosage is 2-3 drops of a 0.1% solution or 1 spray into each nostril 1-3 times a day as required, with a maximum duration of use of 7 days. Caution is advised for children under 12 years, as use is generally not recommended in younger children.

Adults: For adults, the usual dosage is 0.1% solution, administered as 1 spray into each nostril up to 3 times a day as required, with a maximum duration of use of 7 days.

Mechanism of action

Xylometazoline acts as an alpha-adrenergic agonist, stimulating alpha-1 adrenergic receptors on vascular smooth muscle, leading to vasoconstriction. This action reduces blood flow to the nasal mucosa, decreasing swelling and congestion. The onset of action is rapid, providing quick relief from nasal obstruction.

Pharmacodynamics

The pharmacodynamic effects of xylometazoline include significant vasoconstriction of nasal mucosa blood vessels, which leads to decreased nasal congestion. This effect can last for several hours, making it effective for acute conditions. However, prolonged use may lead to rebound congestion due to tolerance development.

Pharmacokinetics

Xylometazoline is administered intranasally, allowing for localized effects with minimal systemic absorption. Peak plasma concentrations are typically reached shortly after administration, although due to its local action, systemic effects are usually minimal. The metabolism and elimination pathways are not well characterized but are believed to involve hepatic metabolism and renal excretion.

Contra-indications

• Hypersensitivity to xylometazoline or any of its excipients
• Severe cardiovascular disease
• Closed-angle glaucoma
• Children under 6 years of age

Adverse effects

• Cardiovascular effects
• Headache
• Hypersensitivity reactions
• Nasal dryness
• Nausea
• Paresthesia
• Visual impairment
• Rebound congestion (rhinitis medicamentosa) with prolonged use
• Agitated psychosis, ataxia, hallucinations, and rare fatalities in infants and children under 6 years

Interactions

• Other sympathomimetics
• Vasoconstrictors

Precautions

• Use with caution in patients with diabetes mellitus
• Hypertension
• Hyperthyroidism
• Prolonged use should be avoided to prevent rebound congestion

Pregnancy

Manufacturer advises avoiding use during pregnancy due to insufficient data on safety.

Breast-feeding

Manufacturer advises caution as no information is available regarding the safety of xylometazoline during breastfeeding.

Storage

Store below 25°C. Do not freeze. Keep the container tightly closed.

Formulations

• {'name': 'Otrivine', 'type': 'Nasal spray', 'strength': '0.1%', 'volume': '15 ml'}
• {'name': 'Sudafed Sinus-Ease', 'type': 'Nasal drops', 'strength': '1 mg per 1 ml', 'volume': '10 ml'}

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

• Nasal congestion due to rhinosinusitis
• Allergic rhinitis
• Non-allergic rhinitis
• Common cold-related nasal congestion

Dosage

Adults: For adults, the typical dose is 0.1% to

Mechanism of action

Xylometazoline acts primarily as an agonist at α_2B-adrenergic receptors, with additional activity at α_1A-, α_2A-, α_2C-, α_1B-, and α_1D-adrenergic receptors. This agonistic action leads to vasoconstriction of the blood vessels in the nasal mucosa, decreasing nasal resistance during breathing and enhancing airflow. The drug's vasoconstrictive properties also contribute to symptomatic relief of associated conditions, such as earache and sore throat, which may arise from mouth breathing due to nasal congestion.

Pharmacodynamics

Xylometazoline is effective in reducing nasal congestion, with a median onset of relief approximately 1.7 minutes after administration and peak relief at around 30 minutes. Its vasoconstrictive effect can lead to rebound swelling and congestion if used long-term, with potential for rhinitis medicamentosa. The drug also exhibits antioxidant properties, which may protect against oxidative stress associated with inflammation in the nasal passages.

Pharmacokinetics

Xylometazoline is rapidly absorbed when administered nasally, although specific pharmacokinetic parameters such as half-life and bioavailability are not well-documented. Its effects are relatively short-lived, necessitating careful management of dosing to avoid rebound congestion. Regular use past the recommended duration can lead to diminished efficacy and increased risk of adverse effects.

Adverse effects

• Rebound congestion
• Nasal mucosa irritation
• Dryness of the nasal mucosa
• Headache
• Nausea

Interactions

• volatile halogenated anesthetics + xylometazoline: Unknown (additive effect)

Precautions

• Use with caution in patients with cardiovascular disease
• Use with caution in patients with hypertension
• Use with caution in patients with hyperthyroidism
• Avoid prolonged use to prevent rebound congestion

Pregnancy

Use during pregnancy only if clearly needed, as safety in pregnancy has not been established.

Breast-feeding

Use with caution, as it is not known whether xylometazoline is excreted in human milk.

Storage

Store below 30°C. Protect from light.

Formulations

• Nasal spray
• Nasal drops

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

Nasal congestion is caused by various etiologies, such as rhinosinusitis and allergic or non-allergic rhinitis, leading to congestion of the venous sinusoids lining the nasal mucosa. Activation of α-adrenergic receptors leads to vasoconstriction of the blood vessels of the nasal mucosa and resumption of nasal airflow. As the most abundantly expressed in the human nasal mucosa, α_1A- and α_2B-adrenoceptors may play the most important role in vasoconstriction of the human nasal mucosa. Xylometazoline is a more selective agonist at α_2B-adrenoceptors, with affinity at α_1A-, α_2A-, α_2C-, α_1B-, and α_1D-adrenoceptors. Xylometazoline decreases nasal resistance during inspiration and expiration and increases the volume of nasal airflow. Compared to [oxymetazoline], another imidazoline nasal decongestant, xylometazoline had a slightly faster onset of action although they had a similar duration of action. In one study, subjects with nasal congestion reported relief of earache and sore throat in addition to nasal decongestion: it is speculated that oxymetazoline mediates this effect by causing vasoconstriction of the nasal mucosa that contains the venous sinuses and nasal decongestion allows breathing through the nose, providing relief from sore throat caused by mouth breathing that dries and irritates the throat.

Pharmacodynamics

Xylometazoline is a sympathomimetic agent that causes vasoconstriction of the nasal mucosa. In one study comprising subjects with nasal congestion associated with the common cold, the median time of onset of subjective relief of nasal congestion was about 1.7 minutes and the time of subjective peak relief of nasal congestion was 30 minutes. Previous studies reported rebound swelling, rebound nasal congestion, rhinitis medicamentosa, and shorter duration of decongestant effect from the long-term use of xylometazoline in healthy volunteers, suggesting that the drug is most effective if used temporarily. An early _in vitro_ study demonstrated xylometazoline to exert anti-oxidant actions, where it inhibited microsomal lipid peroxidation and mediated hydroxyl radical scavenging activity. This suggests that xylometazoline has a beneficial effect against oxidants, which play a role in tissue damage in inflammation.