Why is my mum seeing things?

QMy mum has macular degeneration and her eyesight is gradually getting worse. But in recent months, she’s started seeing things that aren’t there. Other than this, she seems completely normal – are the two linked?

AIt sounds as if your mother has Charles Bonnet syndrome, a common but little-known condition that can affect people with failing eyesight. People with Charles Bonnet have visual hallucinations, especially in dim light or when resting. Interestingly, these don’t tend to occur when the person is falling asleep.

Hallucinations connected with other conditions, such as schizophrenia or dementia, often involve voices or smells. In Charles Bonnet, they are only visual. They can be in colour or black and white; and typically feature faces, animals, plants or abstract patterns. While the faces are often of people familiar to the person, they don’t speak.

These hallucinations can last from seconds to hours, and can be extremely distressing. But many people learn to live with them once they realise the visions aren’t real.

The condition is under-reported, but probably affects almost half of people with severe visual loss and up to one in seven with moderate vision loss. No one is quite sure why it happens, but it might be the brain filling the gap that’s left from reduced visual stimulation with its own images.

Although there is no cure, symptoms often settle within a couple of years. In the meantime, reassurance that the person isn’t going mad, encouraging them to spend as much time as possible in company, and installing brighter lights at home can all help.

QI’ve taken the combined contraceptive pill for more than 20 years because of heavy periods. Are there any health risks to taking it for so long, and will my heavy periods return if I stop it?

AThe health risks of long-term combined oral contraceptive pill use are a common concern among my patients, but I am usually able to reassure them. The pill can increase your risk of a clot on the leg or lung, but in real terms this risk is very small unless you have other risk factors, like smoking. It may also increase the risk of breast and cervical cancer, but again the ‘absolute’ risk is small and disappears within a few years of stopping it. On the plus side, the pill protects against ovarian cancer.

Whether your heavy periods would return if you stopped taking the pill depends to an extent on the cause (fibroids, for example). However, periods often become heavier and more erratic in the years leading up to the menopause anyway, and the pill usually helps to prevent this.

So unless you have any risk factors – and your GP can offer advice about these – there’s no reason why you shouldn’t continue to use the pill until you reach the menopause.