A Question of Health: I fainted on the loo

I AM a 57-year-old man who has recently been diagnosed with micturition syncope. On several occasions I have collapsed in the middle of the night while standing at the toilet emptying my bladder. The first time, I hit my head quite badly on the lavatory bowl. I'm told this is not a serious condition, but it seems potentially quite dangerous to me. Can it be cured?

Micturition syncope - fainting while you are having a pee - is caused by the sudden drop in blood pressure that occurs while your bladder is emptying. It is surprisingly common, although many men simply feel a bit dizzy and do not lose consciousness. As far as I am aware, it affects women only rarely, and this fact provides a clue about how to prevent it happening again. When you get out of a warm bed, your circulatory system is in a relaxed state. As you stand up, your blood pressure is unable to readjust itself quickly enough to maintain a steady supply of blood to the brain. This, in combination with the physiological effect of a bladder contraction, causes you to become dizzy and lose consciousness. Women are not affected by this because they empty their bladders in the sitting position. I recommend that, in the middle of the night, you follow their example.

MY ELDERLY mother takes four different kinds of tablets - two for her blood pressure, one to regulate her heartbeat, and aspirin. She gets repeat prescriptions each month, but it is not uncommon for the chemist to give her a new brand of tablet which is often a different size or colour. She finds this extremely confusing and sometimes mixes up her tablets. The chemist says he is unable to do anything about this, and the doctor says I should take it up with the chemist. Is there no way to stop this lunacy?

Your mother is a victim of generic prescribing. The doctor is prescribing the medications by their generic (chemical) name, and the chemist is entitled to dispense whatever brand he wishes. In practice, chemists change their suppliers according to availability and price. Either ask the doctor to prescribe the tablets by brand name, or change to a chemist who will guarantee to supply the same brand each time. Another idea is to get your mother a Medidos box (available from chemists for about pounds 10). This has compartments into which you can put a whole week's supply of tablets, allowing your mother to take her pills at the right time without thinking about what colour they are.

HOW ACCURATE are home blood pressure monitors?

There are lots of electronic monitors available - finger monitors, wrist monitors and upper arm monitors. Most have not been independently tested for accuracy and therefore cannot be recommended. The British Hypertension Society has validated the Omron HEM 705-CP monitor, and Omron also make other models that use the same scientific principle. Finger monitors may be less accurate than arm or wrist monitors.

Please send your questions to A Question of Health, `The Independent', 1 Canada Square, Canary Wharf, London E14 5DL; fax 0171-293 2182; or

e-mail to health@independent. co.uk. Dr Kavalier regrets he is unable to respond personally to questions