Generic
Permethrin
8 brands available in the market
At a glance
Permethrin is a topical scabicidal agent used for the treatment of scabies and crab lice infestations (Pediculosis). It acts on the nerve cell membrane to disrupt the sodium channel current, resulting in paralysis of the pests.
Description
Permethrin cream contains Permethrin, a pyrethroid, which is a topical scabicidal agent for the treatment of infestation with Sarcoptes Scabiei (scabies). It acts on the nerve cell membrane to disrupt the sodium channel current by which the polarization of the membrane is regulated. Delayed repolarization and paralysis of the pests are the consequences of this disturbance.
Indications
- Scabies
- Crab lice infestations (Pediculosis)
Therapeutic class
Parasiticidal preparations
Pharmacological class
Topical Scabicidal (Pyrethroid)
Pharmacology
Permethrin is a pyrethroid that disrupts sodium channel current on the nerve cell membrane, causing delayed repolarization and paralysis of the parasite. It is minimally absorbed through the skin (<0.5% over 48 hours) and rapidly metabolized in the liver, excreted primarily in urine.
Mechanism of action
Causes parasite paralysis by disrupting sodium channels on nerve cell membranes.
Dosage
Adult Dose (Topical):
- Adults and children over 12 years: 1 full tube
- Children aged 6-12 years: up to ½ tube
- Children aged 1-5 years: up to ¼ tube
- Children aged 2 months to 1 year: up to ⅛ tube
- Children less than 2 months: Dose not established
Administration
- Skin should be clean, cool, and dry before application; do not have a hot shower or bath before applying
- Adults and children over 2 years: Apply cream to the whole body from the neck down, rubbing lightly into the skin until the cream disappears
- Babies under 2 years: Apply to face, neck, ears, and scalp as well, avoiding area around eyes and mouth
- Leave cream on for at least 8 hours before washing off
- If necessary, use again after 7 days as per doctor's advice
Missed dose
If you miss an application, apply it as soon as you remember; skip if it's almost time for the next application; do not double the dose.
Side effects
Side Effects:
- Skin discomfort (burning, stinging, or tingling)
- Erythema
- Edema
- Eczema
- Rash
- Pruritus
Precautions & warnings
- Scabies infestation is often accompanied by pruritus, edema, and erythema; treatment may temporarily exacerbate these conditions
- Avoid contact with eyes; if the cream gets in the eyes, flush with water immediately
- Use in pregnancy only under medical advice
- Should not be used in nursing mothers
Contraindications
- Known hypersensitivity to any component of pyrethroids or permethrin
Drug interactions
- Corticosteroids (for eczematous reactions): Should be withheld prior to permethrin treatment (risk of exacerbating scabies infestation by reducing immune response to the mite)
Food interactions
Not food-related (topical use).
Use in pregnancy
Use in Pregnancy: In the absence of specific studies in pregnant women, use only under medical advice.
Pregnancy Category: B — always consult a doctor before taking during pregnancy.
Use in lactation
Use in Lactation: It is not known whether permethrin is excreted in human milk; should not be used in nursing mothers.
Pediatric use
Dose not established in children under 2 months.
Geriatric use
Caution required in elderly patients; consult your doctor.
Renal / hepatic impairment
Caution required in kidney and liver disease; consult your doctor.
Overdose effects
No overdose information available; consult your doctor if overused.
Storage conditions
Store in a cool, dry place, away from light; keep out of reach of children.
Chemical structure
Permethrin