I'm cursed with 'dry eyes', increasingly making use of celluvisc drops. It worsens with bright sunshine and strong winds, PC use (I'm a writer), weightlifting and alcohol. Are the latter news to you? Any suggestions?

Dry eye is difficult to treat. You aren't making enough tears to keep the surface of your eyes moist. The standard treatment is to use artificial tears, one version of which you have been prescribed. There is no satisfactory way of increasing tear production, so the only advice I can give is to keep well hydrated - drink plenty of water. The connection with alcohol is dehydration - so alternate each alcoholic drink with a long soft drink, preferably water, and don't drink so much that you dehydrate yourself.

For about a year, I have been getting a strong, prickly, tingling feeling in my feet which is particularly bad at night and disrupts my sleep. My doctor suggested iron deficiency as a cause, but a test proved negative. I fell and broke my right foot four years ago and wrenched the other sideways, straining the ligaments. Could this be the cause?

Tingling in the extremities suggests a problem with the circulation or with the nervous system. Either could have been damaged by the injuries to the feet, but it is unlikely that the problem would arise four years later. The fact that it disturbs your sleep suggests a circulation problem, however, perhaps in your arteries, so you should ask about that possibility. Do talk to your doctor again.

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