Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Cream, External:
Elimite: 5% (60 g) [contains formaldehyde solution]
Generic: 5% (60 g)
Pharmacology
Mechanism of Action
Inhibits sodium ion influx through nerve cell membrane channels in parasites resulting in delayed repolarization and thus paralysis and death of the pest
Pharmacokinetics/Pharmacodynamics
Absorption
≤2%
Metabolism
Hepatic via ester hydrolysis to inactive metabolites
Excretion
Urine
Use: Labeled Indications
Head lice (lotion/cream rinse): Treatment of head lice (Pediculus humanus capitis) and its nits (eggs).
Scabies (cream): Treatment of scabies (Sarcoptes scabiei) infestation.
Use: Off Label
Pubic lice (Pediculosis pubis)yes
Based on the Centers for Disease Control and Prevention (CDC) sexually transmitted diseases treatment guidelines, permethrin is an effective and recommended alternative treatment for P. pubis (ie, pubic lice).
Scabies, crusted (Norwegian scabies)yes
Based on the CDC sexually transmitted diseases treatment guidelines, permethrin 5% cream, in combination with ivermectin, is an effective and recommended treatment regimen for crusted scabies (ie, Norwegian scabies).
Contraindications
Hypersensitivity to any pyrethroid or pyrethrin, or to any component of the formulation.
OTC labeling (cream rinse/lotion): When used for self-medication, do not use on infants <2 months of age; near the eyes; inside the nose, ear, mouth, or vagina. Consult health care provider for use on eyebrows or eyelashes.
Dosage and Administration
Dosing: Adult
Head lice: Topical: Cream rinse/lotion 1%: Prior to application, wash hair with conditioner-free shampoo; rinse with water and towel dry. Apply a sufficient amount of lotion or cream rinse to saturate the hair and scalp (especially behind the ears and nape of neck). Leave on hair for 10 minutes (but no longer), then rinse off with warm water; remove remaining nits with nit comb. A single application is generally sufficient; however, may repeat 7 days after first treatment if lice or nits are still present.
Pubic lice (off-label use): Topical: Cream rinse 1%: Apply to affected areas and wash off after 10 minutes (CDC [Workowski 2015]).
Scabies: Topical: Cream 5%: Thoroughly massage cream (30 g for average adult) from head to soles of feet; leave on for 8 to 14 hours before removing (shower or bath); for infants and the elderly, also apply on the hairline, neck, scalp, temple, and forehead; may repeat if living mites are observed 14 days after first treatment; one application is generally curative.
Scabies, crusted (Norwegian scabies) (off-label use): Topical: Cream 5%: Apply to entire body; leave on for 8 to 14 hours before washing off with water. Repeat this regimen daily for 7 days, and then twice weekly until symptoms have resolved. Ivermectin should be given concomitantly on days 1, 2, 8, 9, and 15 (and potentially on days 22 and 29 for severe cases) (CDC [Workowski 2015]).
Dosing: Geriatric
When treating scabies in elderly patients, also apply on the hairline, neck, scalp, temple, and forehead. Refer to adult dosing.
Dosing: Pediatric
Head lice: Note: Usual first-line treatment (or pyrethrins) if community resistance is not an issue (AAP [Devore 2015]); Infants ≥2 months, Children, and Adolescents: Topical: Solution/rinse 1%: After hair has been washed with shampoo (nonconditioning), rinsed with water, and towel dried, apply a sufficient volume of permethrin solution/rinse to saturate the hair and scalp; also apply behind the ears and at the base of the neck; leave on hair for 10 minutes before rinsing off with water; remove remaining nits. May repeat in 7 to 10 days if live lice or nits observed; optimal time to repeat is at day 9 based on the life cycle of lice (AAP [Devore 2015]).
Pubic lice: Limited data available: Adolescents: Topical: Solution/rinse 1%: Apply to affected area, leave on for 10 minutes, then wash off (CDC [Workowski 2015])
Scabies: Infants ≥2 months, Children, and Adolescents: Topical: Cream 5%: Apply and massage in cream from head to toe (average adult requires 30 g); leave on for 8 to 14 hours before washing off with water; for infants, also apply on the hairline, neck, scalp, temple, and forehead; may reapply in 14 days if live mites appear.
Administration
Avoid contact with eyes and mucous membranes during application. Because scabies and lice are so contagious, use caution to avoid spreading or infecting oneself; wear gloves when applying. For the treatment of head lice, use as a portion of a whole lice removal program, which includes 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; items that cannot be washed should be sealed in a plastic bag for ≥4 weeks. Refer to manufacturer’s labeling for additional information.
Cream 5%: Apply to skin from head to soles of feet. Remove cream after 8 to 14 hours (shower or bath).
Cream rinse/lotion 1%: Shake well before using. Apply immediately after hair is shampooed (without conditioner), rinsed, and towel-dried. Apply enough product to saturate hair and scalp (especially behind ears and on nape of neck). Leave on hair for 10 minutes (but no longer) before rinsing with warm water. Remove nits with fine-tooth comb. Protect eyes with a washcloth or towel.
Storage
Store at 20°C to 25°C (68°F to 77°F).
Drug Interactions
There are no known significant interactions.
Adverse Reactions
1% to 10%:
Central nervous system: Local discomfort (scalp), localized burning, localized numbness, tingling of skin
Dermatologic: Pruritus, erythema, skin rash (scalp), stinging of the skin
Local: Localized edema
Warnings/Precautions
Concerns related to adverse effects:
- Skin irritation: Treatment may temporarily exacerbate the symptoms of itching, redness, and swelling. Discontinue use if hypersensitivity occurs.
Other warnings/precautions:
- Appropriate use: For external use only. Avoid contact with eyes.
- Ragweed allergy (cream rinse/lotion): May cause difficulty in breathing or an asthmatic attack.
Pregnancy
Pregnancy Risk Factor
B
Pregnancy Considerations
Adverse events have not been observed in oral animal reproduction studies. The amount of permethrin available systemically following topical application is ≤2%. The CDC considers the use of permethrin or pyrethrins with piperonyl butoxide the drugs of choice for the treatment of pubic lice during pregnancy; permethrin is the preferred treatment of scabies during pregnancy (CDC [Workowski 2015]).
Patient Education
What is this drug used for?
- It is used to treat scabies and lice. It may be given to you for other reasons. Talk with the doctor.
Frequently reported side effects of this drug
- Itching
- Application site irritation
Other side effects of this drug: Talk with your doctor right away if you have any of these signs of:
- Burning or numbness feeling
- Eye irritation
- Signs of a significant reaction like wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat.
Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.
Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.