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Synthetic Pyrethroid (Antiparasitic) Pregnancy: Compatible — safe to use in pregnancy

Permethrin

Brand names: Lyclear (5% cream)

Adult dose

Dose: Scabies: 5% cream applied to entire body surface from neck down (including scalp/face in elderly/immunocompromised), left on for 8–12h, then washed off. Repeat after 7 days.
Route: Topical
Frequency: 2 applications, 7 days apart
Max: Single tube per application for adults
All household contacts must be treated simultaneously. Wash and hot-tumble-dry clothing and bedding on treatment day. Treat any itch that persists >4 weeks post-treatment with crotamiton (not another course of permethrin).

Paediatric dose

Route: Topical
Frequency: 2 applications, 7 days apart
Max: Age-appropriate amount
Concentration: 5% cream Cream/ml
Children ≥2 months: apply to entire body surface including face, scalp, and ears. Avoid eyes and mouth. Children <2 months: seek specialist advice.

Dose adjustments

Renal

N/A

Hepatic

N/A

Clinical pearls

  • Post-scabies itch: continues for 4–6 weeks after successful treatment (dead mite body parts cause ongoing immune reaction) — treat with crotamiton cream or antihistamines; do NOT retreat early
  • Treat all contacts simultaneously — even asymptomatic contacts
  • Crusted (Norwegian) scabies: requires oral ivermectin + topical permethrin under specialist supervision
  • Malathion 0.5% alcoholic lotion: alternative to permethrin if first-line fails

Contraindications

  • Age <2 months
  • Hypersensitivity to pyrethrins

Side effects

  • Skin irritation and burning (first application)
  • Transient worsening of itch (post-scabies itch is common for 4 weeks after treatment)
  • Contact sensitisation (rare)

Interactions

  • None significant

Monitoring

  • Symptom resolution at 4 weeks
  • Identification and treatment of contacts
  • Persistence of itch (distinguish treatment failure from post-scabies itch)

Reference: BNFc; BNF; NICE NG225; PHE Scabies Guidance. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

Pathways