I study regularly with a friend, aged 19, who faints from time to time. Serious causes for the faints have been ruled out – she's had EEGs and brain scans, which have been normal. What worries us is that she drives her car between her digs and college. We suspect that she had a brief faint when at the wheel last week, when she bumped against a kerbstone. Do people faint at the wheel? Should she continue to drive under these circumstances?
Eight years ago, doctors working in Hamburg followed up 104 people referred to them because they had unexplained faints. Three had actually fainted while driving, crashing their cars. Only seven stopped driving of their own accord. Of 95 who were asked to stop, none agreed – they all continued to drive. Within the next year, 19 of them had further fainting attacks while driving, causing injuries to two of them. I haven't read of any similar studies, but I would be unhappy to be a passenger in your friend's car until I knew that her consultant and GP had cleared her for driving. She needs to have a serious discussion with them about whether or not she should drive.

I am overweight, get very depressed and have acne at the age of 28. I just can't stop eating potatoes and pasta: it's as if I have a craving for them. My doctor has taken blood for ovary tests and wants me to have an ultrasound examination. She mentioned polycystic ovary syndrome, but do you think she may suspect cancer, too?
No, you have the classical signs and symptoms of polycystic ovary syndrome, and that's what your doctor is checking for. If you do have it, you can be offered several ways of treating it, including changing your lifestyle, as well as hormone treatment. You may also need checks for high blood pressure and for your risk of developing type 2 diabetes. Don't worry – and please don't blame yourself for your excessive appetite: it is part of your illness, and can be helped, too.

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