What it isPyrethroid that prolongs arthropod sodium-channel opening; scabies and head lice.
Why this oneTopical use is first-line for scabies in pregnancy and young children because systemic absorption is minimal.
What limits itItching can persist after successful treatment and be mistaken for failure; treat close contacts and contaminated bedding together.
FDA-approved for
Off-label
- crusted (Norwegian) scabies with oral ivermectin
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
| Scabies | adults & children | | single application (~30 g for average adult) | |
Renal Undefined
Hepatic Undefined
One application is generally curative.
Instructions
- Thoroughly massage into skin from head to soles of feet
- In infants also apply to scalp, temple, and forehead
- Wash off (shower/bath) after 8-14 hours
- Persistent pruritus is usually not treatment failure; retreat only if living mites persist after 14 days
Contraindications
- Known hypersensitivity to any synthetic pyrethroid or pyrethrin
Cautions
- Mild, transient burning/stinging and pruritus after application
- Rare seizures reported (uncommon, none medically confirmed as drug-associated)
Adverse reactions
- Burning/stinging (10%)
- Pruritus (7%)
- Erythema, numbness, tingling, rash (1-2% or less)
- Headache, dizziness, abdominal pain, nausea/vomiting (postmarket)
Pregnancy Pregnancy Category B - animal studies show no fetal harm; use in pregnancy only if clearly needed.
Lactation Undefined
Principal riskItch persists for weeks and is mistaken for failure
Cost, est. cash$5–$150/month
Generic entry1998
Classes and tags
Clinical profile
Therapeutic safety burden0 / 4
Overdose danger0 / 4
Weight-gain liability0 / 4
Sedation liability0 / 4
QT / Torsades0 / 4
Direct muscarinic antagonism0 / 4
Embryofetal risk0 / 4
Legacy pregnancy categoryUnknown / historical label unavailable
Defining liabilityLocal irritation, sensitization or administration-site injury; negligible systemic toxicity at usual use.
Mechanism of action: Permethrin ballicule
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