Americans were warned in the beginning of November 2000, to stop using dozens of remedies containing the stimulant phenylpropanolamine or PPA after it was linked to hundreds of strokes in young women. PPA is used in everyday cold cures in Britain. It is found in such products as Day Nurse, Benylin Day and Night, Sinutab and Mu-Cron.

PPA is a decongestant. It also makes blood pressure rise and fall quickly and is used in slimming aids.

The US Food and Drug Administration (FDA) said that the ingredients could be to blame for up to 500 strokes in people under 50 - those normally considered too young to be affected.

Doctors first warned of the risks as far back as the 1980s after dozens of young women had strokes within days of taking appetite suppressants.

"PPA is not safe," said Laura Bradbard of the FDA, "We have recommended manufacturers stop selling products containing it immediately and we have started the process which will make it unlawful to use it as either a prescription or non-prescription drug. We have had 44 cases reported to us but we know there are many more unreported. This is happening to people aged between 18 and 49 and they just should not be having strokes."

Britain’s licensing body, the Medicine Control Agency have said that it would be investigating the drug and reviewing the situation in the UK. People who are concerned about it are advised to consult their pharmacist.

A spokesman for Smithkline Beecham, which makes the popular Day Nurse said, "We are aware of the FDA action and we are discussing the situation with the MCA."