WE WERE concerned to see that your article about drug-rape referred to our medicine Rohypnol (flunitrazepam) as "the most common drug used in date rape cases".

We welcome measures to encourage people to be on their guard against criminals misusing medicines. But despite widespread media focus on Rohypnol in the UK, we have received no evidence that it is being used in this way.

Medical experts, as well as the police, have advised us that the issue of violent crime concerning drugs is complex and multi-faceted, and involves a number of different substances. This view is supported by a Metropolitan Police report published in June last year entitled "Drug Assisted Sexual Assault".

That report states that "Rohypnol (flunitrazepam) has not been detected in any suspected drug rape samples submitted to the Forensic Sciences Service".

Furthermore, the report comments that focus on Rohypnol has resulted in this medicine being falsely associated with drug-assisted sexual assault. Some complainants actually assume that the medicine has been used on them, whereas this may not have been the case.

As a consequence individuals who believe that that they have been drug-assisted sexually assaulted can assume that they could not have been attacked in this way if Rohypnol had not been present.

Another misconception is that Rohypnol cannot be detected in drinks. Rohypnol is designed so that it dissolves very slowly if added to a drink. As it dissolves, it releases a bright blue dye and particles of tablet float around in the drink.

These characteristics were introduced by Roche to make it more difficult to misuse Rohypnol. Roche believe that these moves will help to protect the quality of life of legitimate patients who need this product, and at the same time help safeguard those who might be at risk from misuse.

RUTH BLAKEY

On behalf of Roche Products Ltd

Welwyn Garden City