Medicines & Supplements A to Z > Permethrin


Last updated on 09/07/2021.

Overview   |   Dosage   |    Side Effects   |   Precautions  |   Tips  |   Where To Buy  

GENERIC NAME: Permethrin



DRUG CLASS: Anthelmintics

SUB CLASS: Pyrethrins and Pyrethroids, scabicides, pediculicides

USED FOR: Scabies, Head pediculosis

– 5% (lotion)
– 1% (cream)

What is Permethrin for?

Permethrin belongs to a class of medications called pyrethroid anthelmintics. It disrupts sodium ion influx in the nervous systems of parasites, causing paralysis and death. It is used in the treatment of scabies and lice infestations.

How to use it?

Permethrin is available as a lotion and a cream that can be used on the skin.
For the treatment of scabies, apply a thin layer of the cream thoroughly over the whole body, and leave on for 8-14 hours before rinsing.
For the treatment of head lice infection, apply a sufficient amount of lotion over the dried hair and scalp, and leave on for 10 minutes before rinsing. This may be repeated after 7-10 days if necessary.

What are the side effects of Permethrin?

Common side effects of Permethrin include skin and scalp irritation, and skin reactions.

Who should not take Permethrin?

People allergic to Permethrin or any component of the formulation.

Pharmacist Tips:

– Avoid contact with eyes and mucous membranes.
– Avoid applying the medication on open wounds.

Common dosing schedule:
Permethrin is applied once weekly.

This schedule is for reference only, adjustments may be made according to individual needs.

Some common medications Permethrin may interact with:
Permethrin has no known interactions with common medications.

Where to buy Permethrin in Hong Kong?

In Hong Kong, Permethrin is an over-the-counter medicine and can be purchased without a prescription from any retail outlet in Hong Kong. This includes grocery stores, convenience stores, medicine shops, and pharmacies. It can also be obtained from doctors. To find a pharmacy near you, refer to the list of pharmacies (“Authorized Sellers of Poisons”) from the Hong Kong Department of Health.

For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at

Need more information?

For detailed information about the use of Permethrin in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.

Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.