Spinosad

Contraindications

Hypersensitivity

Cautions

Contains benzyl alcohol; toxicity and deaths reported in neonates and infants below the age of 6 months with systemic exposure to benzyl alcohol (ie, neonatal gasping syndrome)

Spinosad may be found in some form under the following brand names:

• Natroba

• Spinosad is a 5:1 mixture of spinosyn A and spinosyn D, natural macrocyclic lactones derived from fermentation of Saccharopolyspora spinosa, a soil actinomycete.1 2 5 8 9 12

• Insecticide used as a topical pediculicide.1 2 14

• Interferes with nicotinic acetylcholine receptors and, to a lesser extent, γ-amino butyric acid (GABA) receptors in insects, including lice.1 2 5 8 9 12 Causes extended periods of neuronal hyperexcitation that result in louse paralysis, inability to feed, and death.1 2 5 8 9 12

• Ovicidal at all stages of louse egg development.5 7 Spinosad-resistant lice not documented to date.11

• Active against permethrin-resistant human head lice.5 13 Cross-resistance with other pediculicides not expected.5 13

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

• If you have an allergy to spinosad or any other part of spinosad.
• If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.

This medicine may interact with other drugs or health problems.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this medicine with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

• Store at room temperature. Do not freeze.
• Store in a dry place. Do not store in a bathroom.
• Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
• Check with your pharmacist about how to throw out unused drugs.

• Natroba

Topical suspension; for external use only. Shake bottle well. Apply to dry scalp and rub gently until the scalp is thoroughly moistened, then apply to dry hair; completely covering scalp and hair. Wash hands after application. Leave on for 10 minutes (start timing treatment after the scalp and hair have been completely covered). The hair should then be rinsed thoroughly with warm water. Shampoo may be used immediately after the product is completely rinsed off. If live lice are seen 7 days after the first treatment, repeat with second application. Avoid contact with the eyes. Nit combing is not required, although a fine-tooth comb may be used to remove treated lice and nits.

Spinosad should be a portion of a whole lice removal program, which should include washing or dry cleaning all clothing, hats, bedding and towels recently worn or used by the patient and washing combs, brushes, and hair accessories in hot water.

Store at 25°C (77°F); excursions permitted between 15°C to 30°C (59°F to 86°F).

Dosage form specific issues:

• Benzyl alcohol and derivatives: Some dosage forms may contain benzyl alcohol; large amounts of benzyl alcohol (≥99 mg/kg/day) have been associated with a potentially fatal toxicity (“gasping syndrome”) in neonates; the “gasping syndrome” consists of metabolic acidosis, respiratory distress, gasping respirations, CNS dysfunction (including convulsions, intracranial hemorrhage), hypotension, and cardiovascular collapse (AAP ["Inactive" 1997]; CDC, 1982); some data suggests that benzoate displaces bilirubin from protein binding sites (Ahlfors, 2001); avoid or use dosage forms containing benzyl alcohol with caution in neonates. See manufacturer’s labeling.

Other warnings/precautions:

• Appropriate use: For topical use on scalp and scalp hair only; not for oral, ophthalmic, or intravaginal use. Avoid contact with eyes. Wash hands after application. Should be used as a part of an overall lice management program.