GPs are being urged to warn patients about the dangers of over-applying OTC medications, after a middle-aged woman developed a potentially life-threatening anaemia after using a common vaginal cream.

The perimenopausal woman, 50, developed methaemoglobinaemia after using Vagisil excessively for her severe, chronic vaginal itch, report doctors from Orlando Regional Healthcare in Florida, US.

The culprit ingredient in the cream is benzocaine, known to produce free radicals that can oxidise haemoglobin into methaemoglobin, which is unable to reversibly bind oxygen, they write in BMJ Case Reports.

It’s the fourth reported case of a woman developing the severe anaemia after using a vaginal cream or benzocaine spray, they say.