Derbac M (R)

Last reviewed 01/2018

Malathion is used in the treatment of pediculosis and scabies.

Malathion 0.5% liquid is licensed for children, aged 6 months and above, and adults.

After topical application absorbed malathion is rapidly detoxified by plasma carboxylesterases. Over the next 7 days about 4.5% of a single dose applied to the skin is recovered from the urine.

In the treatment of scabies the British National Formulary recommends malathion should be applied twice, one week apart..

The aqueous solutions are preferred in children and in asthmatics. Alcoholic preparations cause irritation of excoriated skin and the genitalia.

Malathion is not contraindicated in pregnancy or breast-feeding.

The summary of product characteristics should be consulted before prescribing this drug.


  1. Drugs and Therapeutics Bulletin (2002), 40 (6), 43-46.