G-B Benzoate

Approved Indications:

• Scabies (Sarcoptes scabiei infestation): Used topically to treat scabies in adults and children over 2 years.
• Pediculosis (lice infestation): Effective against head lice (Pediculus humanus capitis) and body lice.

Off-label / Clinically Accepted Uses:

• Demodicosis: Sometimes used off-label for Demodex mite infestations, especially in dermatological settings.
• Adjunctive antipruritic treatment: Occasionally employed as part of topical therapies for parasitic-related itching.

Route: Topical (cutaneous application only)

Adults:

• Scabies: Apply a 25% lotion to the entire body from the neck down, usually at night. Leave on for 8–12 hours, then wash off. Treatment may be repeated after 24–48 hours if needed.
• Lice: Apply a 25% lotion to the scalp and hair. Leave for 24 hours and then wash off. A second application may be repeated after 7 days.

Pediatric (Over 2 years):

• Use a diluted 10% preparation. Apply similarly to adult regimens, but avoid mucosal contact and overuse.

Geriatric:

• Same dosing as adults, with monitoring for potential skin irritation.

Special Populations:

• Renal/Hepatic impairment: No systemic involvement; dosing is topical with minimal absorption. Caution is still advised due to potential skin sensitivity.

Administration Notes:

• Do not apply to inflamed, broken, or eczematous skin.
• Avoid contact with eyes, mucous membranes, and open wounds.
• Always wash off thoroughly after recommended duration.
• Clothing and bedding should be cleaned to prevent reinfestation.

Benzyl benzoate acts as a toxic agent to the nervous system of mites and lice. It penetrates the parasite’s exoskeleton and causes neurotoxic effects leading to paralysis and death. The precise molecular mechanism is not fully understood but involves mitochondrial disruption and inhibition of vital enzymatic processes in arthropods. Its rapid miticidal and pediculicidal action makes it effective for short-term topical treatment of parasitic infestations.

• Absorption: Minimally absorbed through intact skin; higher absorption through damaged or inflamed areas.
• Distribution: Localized to the application site; not systemically distributed under normal conditions.
• Metabolism: Metabolized in the liver to benzoic acid and benzyl alcohol.
• Excretion: Metabolites are excreted primarily in the urine.
• Onset of Action: Relief of symptoms (itching) may begin within hours after application.
• Half-life: Not clinically significant due to limited systemic absorption.
• Bioavailability: Very low when applied to intact skin.

• Pregnancy: Classified as Pregnancy Category C (risk cannot be ruled out). Use only if clearly needed and benefits outweigh potential risks. Data on teratogenicity in humans are lacking.
• Lactation: Unknown whether excreted in human breast milk. Avoid application on or near the breast to prevent infant ingestion. Use with caution and under medical advice.
• Recommendation: Avoid use during pregnancy and lactation unless essential.

• Primary Class: Scabicide and Pediculicide
• Subclass: Topical Ectoparasiticide

• Hypersensitivity to benzyl benzoate or any component of the formulation.
• Acute dermatitis or severely inflamed, broken skin.
• Neonates and infants under 2 years of age.
• Known allergy to benzoates or ester compounds.

• Irritant Potential: Can cause severe skin irritation, especially in young children and people with eczema.
• Ocular Risk: Avoid contact with eyes; may cause burning and conjunctivitis.
• Neurological Risk: Inappropriate use (e.g., ingestion or excessive application) may lead to systemic toxicity, especially in children.
• Secondary Infections: Avoid use over broken skin to prevent systemic absorption and secondary infections.
• Flammability: The alcohol-based solution is flammable. Keep away from flames and heat sources.

Common Side Effects (Dermatologic):

• Skin irritation
• Itching or burning sensation
• Erythema
• Stinging at application site

Serious/Rare Adverse Effects:

• Allergic contact dermatitis
• Blistering or vesiculation
• Systemic neurotoxicity (in rare cases of overdose or improper use)
• Secondary bacterial infection from over-irritation

Timing and Severity:

• Most side effects occur shortly after application and are localized.
• More severe reactions typically occur with misuse or hypersensitive skin.

• Topical Corticosteroids: May reduce efficacy by decreasing inflammatory response needed for parasite detection.
• Other Topical Irritants (e.g., sulfur, salicylic acid): Concurrent use may increase irritation or skin barrier disruption.
• Systemic Interactions: None known due to minimal systemic absorption.

Enzyme Interactions: Not metabolized via CYP450 system; no known hepatic enzyme interaction.

• No significant changes in approved indications or formulation in recent guidelines.
• WHO and CDC still include Benzyl Benzoate as a recommended treatment for scabies, especially in low-resource settings.
• Alternative agents (e.g., permethrin, ivermectin) may be preferred in high-resource countries due to better tolerability, but Benzyl Benzoate remains a first-line option in many guidelines where cost-effectiveness is prioritized.

• Temperature: Store below 25°C (77°F).
• Light Protection: Keep in a tightly closed container, away from direct light.
• Humidity: Store in a dry place; avoid moisture.
• Handling: Shake well before use if in suspension or emulsion form.
• Reconstitution: Not required.
• Special Precautions: Keep away from open flame or heat. Keep out of reach of children.