If a family is going to enjoy an expedition despite one of its members suffering from travel sickness the preparations to defeat this must start hours before they set off. It is no good giving children their treatment as one of the last-minute details, like setting the burglar alarm, before leaving.

The reader’s sons are too young to use hyoscine transdermal patches, such as Scopoderm. (Hyoscine is a drug used to dry up secretions and thereby stops people from feeling sick — it is related to atropine, which many will have had before surgery.) However, many adults find that one of these put on to a hairless patch of skin behind the ear five or six hours before the journey will slowly release its load for 72 hours. This should allow the traveller to reach Australia, or to sail across the Channel without mishap.

Some adults should also avoid hyoscine. It is not recommended for the pregnant, for the elderly, for men with prostatic problems, for those with raised eye pressure (glaucoma) and it occasionally causes confusion and drowsiness even in the fit and young. Hyoscine doesn’t mix well with alcohol.

For adults and children above the age of 5 my favourite alternative to a transdermal patch is Stugeron cinnarizine tablets (the patches and tablets are available over the counter). Stugeron is a long-established antihistamine. It needs to be taken only two hours before setting off and doesn’t have to be repeated for another eight. This should deal with lunch and tea at the boys’ grandmother’s and the return journey.

For long trips try to start early in the morning or late in the evening, when children are a bit sleepy. With luck they might drop off to sleep. Incidentally, the mode of transport least likely to cause travel sickness is the railway. If driving, forget the winding scenic route and choose a road that is straight, boring and with an even surface.

Find some in-car entertainment that doesn’t involve reading, and avoid family games such as 50p for the first child to spot a man with a beard or a whippet as these encourage children to watch the passing countryside giddily flashing past. Tapes and DVDs with stories are excellent at distracting the potentially car sick. Don’t allow tension to rise. Avoid rich foods before setting off and before any return journey. Make certain that the air in the car is circulating and keep the window open.

Grapefruit juice for breakfast and its effect on statins has produced a mailbag of replies and more questions. Typical is the letter from Romford in which the reader is so attached to grapefruit for breakfast that he is not certain that he wouldn’t rather give up simvastatin (Zocor and Inegy) than the juice.

It is possible to find statins that can be taken with grapefruit juice. I was wrong in a previous column to include Crestor (rosuvastatin) among the statins that shouldn’t be taken with grapefruit juice, or at any time during the day in which grapefruit juice has been drunk. Crestor is metabolised by a slightly different pathway from Lipitor (atorvastatin) or Zocor (simvastatin). Lipostat (pravastatin) is another statin that can be taken with grapefruit juice.

Crestor is a very effective statin, relatively recently introduced. Only a small dose of it is needed to control cholesterol levels. For this reason the starting dose is smaller than with the other statins and needs to be gradually increased while its effect on various enzymes in the blood is checked. The objective in taking statins is to achieve the maximum benefit with the smallest dose possible.

There have been several letters asking abou the occasional side-effect of statins, that is, muscle damage. This is uncommon but as a precaution enzymes are carefully checked when fixing the appropriate dose and from time to time thereafter. This side-effect is more likely in the aged, those with kidney problems or an under-active thyroid, and in those taking other drugs to lower cholesterol levels.

Statins may also interact with other drugs, among them warfarin, and this has to be taken into account.

Send Dr Thomas Stuttaford your questions on diabetes from here.

ASK DR STUTTAFORD

Send your questions to drstuttaford@thetimes.co.uk or to times2, The Times, 1 Pennington Street, London E98 1TT. Please include the following: the symptoms (and how long they have been present), the person’s age, sex and marital status. Dr Stuttaford’s replies cannot apply to individual cases but should be taken in a general context.

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