THE BUSY Marylebone Road makes the Harley Street area one of the most polluted in London. This doesn’t stop people drinking at the tables on the crowded pavements, where they happily defy the high pollen counts and the increasing atmospheric pollution as the temperature reaches Caribbean levels.

As they sip wine or knock back pints of beer, their eyes may redden and their noses run, but they have no sure way of knowing whether it is the alcohol or pollen allergy that is causing the trouble.

June is the month for hay fever. The number of patients suffering from the symptoms of seasonal allergic rhinitis is more than twice as high in an average Juneas it is May and it is 10 per cent higher in June than in July.

If a heat wave strikes early, the combination of an urban polluted atmosphere and a high pollen count is especially trying for patients with an allergic tendency. Just a short walk at this time of the year may result in nasal irritation, congestion and a runny nose, together with sneezing. Patients’ eyes become itchy and red and they may develop a frog in their throat. Some will even notice that their ears are irritated as well.

Many people who suffer also have generalised symptoms, and feel vaguely unwell. One symptom often underrated by non-sufferers is insomnia. Celebrating dawn at Stonehenge on the longest day of the year is all very well for the 80 per cent who don’t have allergic rhinitis. But for those who do, light nights and early dawns make insomnia a real problem — and that’s if they aren’t already being kept awake by snuffling, sniffing and snoring.

Day-time sedation and sleepiness may be exacerbated by the old-fashioned first-generation antihistamines. These are still the basic treatment for hay fever but the older versions, bought over the counter at the chemist, cause sedation. They also depress intellectual performance and may induce irritability while increasing the likelihood of accidents, including car crashes. They do nothing for the A-level results either.

It is better to go to the doctor and obtain a prescription for one of the second-generation antihistamines without the side effects of drowsiness and reduced concentration. They can even be taken with a drink at a Marylebone Road pub.

A study carried out in the Netherlands out several years ago on drugs that could prove a factor in motorway car crashes showed that first-generation antihistamines ranked behind only alcohol or cannabis.

First-generation antihistamines control most of the main symptoms of hay fever but are not successful at easing the nasal congestion, one of the major factors that leads to insomnia. Neoclarityn and Xyzal are among the new second-generation versions that control the congestion as well.

A steroid nasal spray such as Flixonase, Beconase, Nasonex or Rhinocort, taken with either a second-generation antihistamine or as a complete treatment, is another very effective treatment. The sprays avoid the use of oral steroids in most cases. Eye drops may be used as an additional measure.

If the symptoms are so severe that the standard treatments are unsuccessful, it may be necessary for the patient to have annual anti-allergy injections well before the start of the hay fever season. These are now given only in hospitals in case the injection induces a severe reaction.

It is important to try to avoid the allergens in pollens or moulds, especially when treatment isn’t entirely successful. There are several ways to attempt this. Patients should obviously stay indoors as much as possible, but if they need to go out and about they should stay away from grass. The pavements of Marylebone or Soho are healthier than the grass of Regent’s Park. When out of doors sufferers should wear sunglasses to protect the eye mucosa from pollen, and when indoors they should keep windows closed.

Sufferers from hay fever should have a bath or shower in the evening to wash the pollen off their skin before going to bed and, hopefully, to sleep.

E-mail Dr Thomas Stuttaford your questions on hay fever