SCABOMA CREAM

Indications

• Topical anesthesia for minor skin irritations
• Sore throat relief
• Dental procedures

Dosage

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

Adults: Apply a thin layer to the affected area as needed, not exceeding the recommended frequency in product guidelines.

Mechanism of action

Benzocaine diffuses into nerve cells where it binds to sodium channels, preventing the channels from opening, and blocking the influx of sodium ions. Nerve cells unable to allow sodium into cells cannot depolarize and conduct nerve impulses. Benzocaine reversibly stabilizes the neuronal membrane, decreasing its permeability to sodium ions, thereby inhibiting depolarization of the neuronal membrane and blocking the initiation and conduction of nerve impulses.

Pharmacodynamics

Benzocaine is indicated for use as a topical anesthetic. It has a duration of action of approximately 10 minutes and a wide therapeutic window. Patients should be counselled regarding the risks of methemoglobinemia, a rare but serious condition that can occur with excessive use.

Pharmacokinetics

Benzocaine is poorly soluble in water, which limits its systemic absorption when applied topically. It is rapidly absorbed through the skin, and its effects are localized. The half-life and metabolism details are not extensively documented, but the drug is primarily metabolized in the liver. Clearance from the system generally occurs within a short time frame, correlating with its brief duration of action.

Adverse effects

• Methemoglobinemia
• Allergic reactions
• Local irritation
• Skin rash

Precautions

• Use with caution in patients with a history of methemoglobinemia
• Not for use on large areas of damaged skin or mucous membranes
• Avoid contact with eyes

Pregnancy

Benzocaine should be used in pregnancy only if the potential benefit justifies the potential risk to the fetus. Consult a healthcare professional.

Breast-feeding

Benzocaine is generally considered safe for use during breastfeeding, but caution is advised. Consult a healthcare professional for specific recommendations.

Storage

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

Formulations

• Topical cream
• Topical gel
• Topical ointment
• Lozenges

Indications

• Scabies
• Pediculosis (lice infestation)

Dosage

Children: For scabies in children over 2 years, apply lindane lotion or cream to the affected areas for 8 to 12 hours before washing off. For lice, apply to dry hair and scalp, leave for

Adults: For scabies, apply lindane lotion or cream to the affected areas and leave it on for 8 to 12 hours before washing off. For pediculosis, apply to dry hair and scalp, leave for 4 minutes, then rinse thoroughly. Repeat treatment may be necessary after 7 to 10 days.

Mechanism of action

Lindane exerts its effects by acting as a gamma-aminobutyric acid (GABA) receptor antagonist. It inhibits the GABA-activated chloride channels in the nervous system of insects and other parasites. This inhibition leads to the overstimulation of the nervous system, causing paralysis and death in the targeted organisms. The degradation pathway involves γ-hexachlorocyclohexane degradation.

Pharmacodynamics

As an insecticide, lindane is effective against a variety of ectoparasites, including scabies mites and lice. Its neurotoxic effects stem from its action on the GABA receptor, leading to increased neuronal excitability and subsequent paralysis of the parasites. Lindane's toxicity to non-target organisms, including humans, is a significant consideration in its use.

Pharmacokinetics

Lindane is well absorbed through the skin and gastrointestinal tract. Following topical application, it can be distributed to various tissues, including adipose tissue, where it may accumulate. Lindane is metabolized primarily in the liver, with its metabolites being excreted via urine and feces. The half-life of lindane can vary, but it is generally around 1 to 2 days, with a potential for longer persistence in the body due to fat solubility.

Contra-indications

• Hypersensitivity to lindane or any of its components
• Severe skin conditions
• Concurrent use with other topical insecticides

Adverse effects

• Skin irritation
• Erythema
• Pruritus
• Seizures (in cases of overdosage or inappropriate use)
• Headache
• Dizziness

Interactions

• Caution is advised when used with other neurotoxic agents

Precautions

• Use with caution in patients with a history of seizures
• Avoid use in children under 2 years of age unless directed by a physician
• Do not apply to broken or inflamed skin

Pregnancy

Lindane should only be used during pregnancy if the potential benefit justifies the potential risk to the fetus. Consult a healthcare professional.

Breast-feeding

Lindane is excreted in breast milk. Caution is recommended when administering to breastfeeding mothers.

Storage

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

Formulations

• Topical lotion
• Topical cream
• Shampoo

Mechanism of action

Benzocaine diffuses into nerve cells where it binds to sodium channels, preventing the channels from opening, and blocking the influx of sodium ions. Nerve cells unable to allow sodium into cells cannot depolarize and conduct nerve impulses. Benzocaine reversibly stabilizes the neuronal membrane with decreases its permeability to sodium ions. Depolarization of the neuronal membrane is inhibited thereby blocking the initiation and conduction of nerve impulses.

Pharmacodynamics

Benzocaine is indicated for use as a topical anesthetic. It has a duration of action of approximately 10 minutes and a wide therapeutic window. Patients should be counselled regarding the risks of methemoglobinemia.