Generic Permethrin

Common Use
Permethrin is an antiparasitic medication used to treat infestations such as head lice, scabies, and pubic lice. It works by paralyzing and killing the parasites and their eggs. It is available in cream, lotion, and shampoo forms for external use only.

Dosage and Direction
For scabies, apply the cream to the entire body from the neck down and leave it on for 8 to 14 hours before washing off. For lice, apply the lotion or shampoo to dry hair, leave it for 10 minutes, then rinse thoroughly and comb out dead lice and nits. Follow your healthcare provider’s instructions and do not use more often than recommended.

Precautions
Use permethrin externally only and avoid contact with eyes, mouth, and mucous membranes. Inform your doctor if you have skin conditions like eczema or open wounds. Permethrin is generally safe, but caution is advised in infants and pregnant or breastfeeding women.

Contraindications
Do not use permethrin if you are allergic to pyrethrins, chrysanthemums, or any ingredients in the product. It should not be applied to broken or inflamed skin. Avoid use in newborns without medical supervision.

Possible Side Effects
Mild burning, stinging, redness, or itching at the application site are common. Rarely, allergic skin reactions such as rash or swelling may occur. If symptoms worsen or signs of infection appear, contact your doctor.

Drug Interaction
Permethrin used topically has minimal systemic absorption and is unlikely to interact with other medications. However, inform your doctor of all drugs or skin treatments you are using. Avoid using other topical irritants on the treated area.

Missed Dose
If a treatment is missed, apply it as soon as possible. Do not apply double the amount to make up for a missed treatment. Follow reapplication guidelines based on the condition being treated.

Overdose
Overdose is rare with topical use, but accidental ingestion or excessive application may cause nausea, vomiting, or dizziness. In case of suspected overdose, seek immediate medical help. Treatment is supportive and based on symptoms.

Storage
Store permethrin at room temperature away from heat, moisture, and light. Do not freeze. Keep out of reach of children and avoid storing in the bathroom.

Disclaimer
We provide only general information about medications which does not cover all directions, possible drug integrations, or precautions. Information at the site cannot be used for self-treatment and self-diagnosis. Any specific instructions for a particular patient should be agreed with your health care adviser or doctor in charge of the case. We disclaim reliability of this information and mistakes it could contain. We are not responsible for any direct, indirect, special or other indirect damage as a result of any use of the information on this site and also for consequences of self-treatment.

Clinical Verification

Last Clinically Updated: August 15, 2026

Written By

Dr. Elena Vance, PharmD

Clinical Specialist in Neuropharmacology

Fact Checked By

Marcus Thorne, MS

Biomedical Data & FDA Label Verification

Medically Reviewed By

Dr. Arthur Campbell, MD

Board-Certified Psychiatrist (ABPN)