ONCE again, St Helens Primary Care Trust is to be applauded for its on-going effort to raise public awareness about the dangers associated with the long term use of legally prescribed benzodiazepines such as Lorazepam (Ativan), Diazepam (Valium), Temazepam and Nitrazepam (Want to stop taking sleeping tablets? Star, January 20).

For over 20 years, campaigners have argued that the pharmaceutical companies have suppressed information on the addictiveness and long-term side effects of these drugs in the UK.

Only recently, campaigners in the 'Beat the Benzos' pressure group discovered that Wyeth, who manufacture Lorazepam, had issued warnings in Canada that even a normal dose of benzodiazepines, including Lorazepam, may lead to potentially, fatal respiratory depression. Wyeth's Canadian data sheet also contained a warning that only one week of treatment should be dispensed, automatic repeat prescriptions are not allowed and subsequent prescriptions - when required - should be limited to short courses.

In the early months of 2004, Wyeth finally submitted a variation - warning of these risks - to update the product information of Lorazepam, in line with its revised worldwide prescribing information, to the UK regulatory agencies the Medicines and Healthcare Products Regulatory Agency. The MHRA approved changes to patient information leaflets last September, but decided no public warning was necessary.

Benzodiazepines however have been prescribed for long term use in the UK since 1959 and more than one million people are involuntary addicted to these drugs. In St Helens, prescribing rates have always been far above the national average.

In November 2004, Phil Woolas MP, Deputy Leader of the House of Commons - who is at the forefront of the 'Beat the Benzos' campaign - used his parliamentary privilege at an influential Health Select Committee Inquiry to request that the Committee subpoena documents belonging to the international pharmaceutical companies Roche (manufacturers of Diazepam and Nitrazepam) and Wyeth. Mr Woolas stressed that the over prescription of these drugs has caused enormous damage to people and hopes that the select committee will point the finger at those responsible and point the way forward.

St Helens PCT is amongst only a handful of authorities in the UK to highlight the dangers of long-term use of benzodiazepines and 'Z' drugs, such as Zopiclone, which act in a similar manner. As an ex-involuntary addict I am impressed by this determined course of action and echo the warning that it is dangerous to stop taking these drugs abruptly. Consequently, I continue to hope that enough information, support and reassurance will be made available to local people who wish to begin a slow and safe withdrawal from these addictive drugs.

JOAN Bryant, Elephant Lane, St Helens.