Booklice (or psocids) are a common but harmless insect mainly found outdoors feeding on yeasts, moulds and mildews. They are attracted to warm and damp conditions and can also be found in domestic kitchens as well as food manufacturing and retail premises. Booklice are cream-coloured or light brown and are around 1mm in length and can move very quickly. The female can lay up to 100 eggs in total which are usually found in cracks and crevices. Booklice are not to be confused with body lice.


Although booklice are harmless to humans, the major problem posed by them is the nuisance they cause, as they can be present in large numbers throughout the home. They are not caused by poor hygiene but can be associated with high humidity or anywhere where damp is present. Dampness may result from new plaster work, condensation forming due to lack of ventilation or simply a leaking tap. Whatever the cause, this moisture will allow booklice to thrive. Some foods, including flour, naturally contain some moisture and it is here that booklice are likely to increase rapidly in number. They can also be found attacking a variety of materials including plaster, leather, woodwork and books. Materials of both plant and animal origin may be attacked, but preference is shown to those which are damp and they feed on the moulds and bacteria that develop.

How do I get rid of them?

Firstly, establish the extent of the infestation. Are the booklice restricted to a specific area or are they throughout the house? If the insects are only affecting one particular place, for example, a food cupboard, you may well be able to treat the problem yourself by following this advice:

  • Empty out the contents of the cupboard and inspect each item, paying particular attention to bagged dry foods, such as flour. Any infested goods should be thrown out.
  • Jars and tins are not normally attacked but check that booklice are not behind the labels or around the screw tops of jars.
  • Once the cupboard has been emptied, sweep out any food spillage. If you do need to wash down a cupboard, make sure that it is thoroughly dried.
  • Use a good household insecticide and spray the cupboard. Make sure you spray all the cracks around the shelving as booklice will tend to collect there. Always follow manufacturers instructions carefully.
  • Allow the spray to dry fully and use the cupboard for the storage of non-food stuffs for at least a month.
  • To prevent a booklice infestation, keep the house thoroughly aired and dried. Good ventilation is essential to deter the development of moulds on which they will feed. Repair any leaks to prevent damp and always store dried foods in a cool dry place, preferably in sealed containers.

Unfortunately we don't have a pest control service which treats booklice. In cases where booklice are infesting large areas of your home, you can use a local pest control contractor. We are unable to recommend local pest control firms, but suggest using a service search engine such as Yell. We advise you to get two to three quotes to obtain a competitive price.