The go-to handbook for DIY euthanasia has been outlawed from Australian shores and is being seized upon entry into the country.

A Department of Immigration and Border Protection spokesman said the Peaceful Pill Handbook was not permitted under the Customs (Prohibited Imports) Regulations 1956.

Under the regulations, "documents that promote, counsel, incite, or instruct in the use of a device which is designed or customised to be used to commit suicide are prohibited imports".

"The Australian Border Force assesses goods at the border and will seize prohibited imports," the spokesman told AAP on Sunday.

Exit International says elderly Australians in four states who ordered the book from the Netherlands, where it is published, were told the book was breaching the customs act being a publication "that offend against the standards of morality, decency and propriety generally accepted by reasonable adults".