Arriving in an exotic or even not-so-exotic country can cause havoc for people who suffer from allergies. There's a greater risk of an out-of-the-blue reaction, as well as the difficulties of explaining the problem in a different language to restaurant staff or doctors. Make sure you have a supply of antihistamine tablets.
Some people are at risk from the extreme allergic reaction anaphylaxis, which causes breathing difficulties and can be fatal. If this is a problem, ask your doctor to prescribe you an Epipen, a safe, easy device that contains a shot of adrenalin or epinephrine.
Other countries may not have the same rigorous food-labelling system the UK has regarding nuts and other ingredients, so exercise caution. Consider a medical alert bracelet highlighting allergies, particularly to things such as penicillin or anaesthetics. See www.allergyaction.org for translations of key phrases.
Long-distance air travel and its effects can ruin the start of a holiday and make you wish you'd opted for Cornwall after all. As a rule of thumb, it takes one day to adjust to each hour of time difference, and it seems to take longer if you are flying eastwards.
There are no clinically proven cures for jet lag, but the best advice is to fit in with local times as soon as possible and get some sleep. It may be worth paying extra to get a more convenient flight time; arriving in a country late in the afternoon means that children will have time for a meal and can then hit the sack. Alternatively, getting out in the sunlight will help them to sleep in the evening, and eating a carbohydrate-rich meal, such as pasta, will also aid sleep. Herbalists recommend arnica as a remedy. An arnica-based product, No-Jet-Lag, is available from Boots.
One solution for adults (but not children) may be melatonin, a hormone produced by humans at night that resynchronises the body clock. The jury is still out on whether taking melatonin tablets can cure jet lag. Anyway, it is only available in the United States; its sale is banned in the UK because of fears of health risks, as it is thought that it may interfere with ovulation.
Also known as miliaria, prickly heat is caused excessive perspiration, resulting in a blockage of the sweat glands. The sweat seeps into nearby skin and builds up into tiny pockets of inflammation - the tell-tale rash. Babies are particularly at risk. You can prevent it by avoiding heat and humidity, wearing loose cotton clothing and staying in an air-conditioned room for a few days. Cold showers, calamine lotion and steroid creams (available from pharmacies) can help to soothe the skin, and the rash normally disappears within a few days.
Up to half of Europeans who spend two or more weeks in parts of the developing world will suffer an attack of diarrhoea. Even destinations closer to home, such as Spain or Greece, can cause problems. Children are more at risk than adults; the most important thing is to replace the fluids they lose with plenty of water mixed with a fruit cordial to provide glucose. For babies, breast-feed rather than use formula milk that needs to be mixed with water.
Unless you know the tap water is safe, drink bottled. When cooking, follow the maxim "peel it, boil it, cook it, shell it or forget it". Bananas can help to stop diarrhoea, and live yogurt will settle the stomach by introducing "friendly" bacteria.
"Blocker" medicines such as Imodium can be useful, but won't treat the symptoms and can extend the length of an attack. Mild diarrhoea can be treated with a natural remedy, ispaghula husk. If diarrhoea lasts longer than a couple of days, see a doctor.
MOTION AND SEA SICKNESS
Motion sickness occurs when the eyes and balance organs in the ears give out conflicting messages about what is happening and the brain becomes confused. Children can be particularly vulnerable and there is little worse than starting a holiday with a sick youngster, so be prepared.
If you can, choose the part of the plane, bus or boat that has the least pitching and rolling movement. For planes, try for a seat between the wings; on a boat, get in the middle and try to look at the horizon rather than close up; in buses, sit at the front and look forwards, not sideways.
Antihistamines can help and will last for about eight hours, but can cause drowsiness. Hyoscine patches, which are applied five to six hours before a journey, won't cause drowsiness but don't last as long as antihistamines. If you prefer natural remedies, ginger can counteract the dry mouth often caused by motion sickness.
Sea-Bands and other travel bands are elasticised bracelets with a plastic stud that presses on an acupuncture point. They can reduce nauseous feelings, although some research has suggested that they are not all that effective.
Despite the warnings about skin cancer, far too many of us hit the beach and the poolside without adequate protection. Follow the Australian rule of Slip, Slap Slop (slip on a shirt, slap on a hat, slop on some suncream) and you won't go wrong.
If you do get sunburn, make sure you have some calamine lotion to soothe the skin. Don't use oily creams as they will simply trap heat in and add to the discomfort. Fluids can be lost through badly burnt skin, so drink plenty of water.
Much more serious - indeed, potentially fatal - is heatstroke, so watch for the symptoms. These include abnormal breathing, a lack of co-ordination, confusion and irrational behaviour. Victims will also stop sweating and, in extreme cases, suffer convulsions.
Place the sufferer in the shade, remove their clothes and sponge them with a cool, wet cloth. Encourage them to drink. Monitor their temperature to ensure that it does not fall too low or rise again.
If your holiday is going to feature a lot of messing about in the sea or the pool, be prepared for swimmer's ear. Also known as otitis externa, this is an infection of the outer-ear canal. It occurs when water becomes trapped in the ear, providing a breeding ground for bacteria. Other causes are humid atmospheres, harsh cleaning of the ear canal and a lack of ear wax.
Symptoms include a red, itchy and painful ear, swollen glands in the neck and hearing loss.
It can be prevented by wearing ear plugs and by placing a few drops of vinegar and water into the ear after swimming. It can be treated with antibiotic drops, but a natural alternative is to put a drop of whisky or gin in the ear several times a day for a few days.
BITES AND STINGS
There are many bugs out there with the potential to disrupt and even ruin your holiday, but you can deal with the most common bites and stings.
* Have a good insect repellent and use it liberally.
* Tiger balm, calamine lotion and even white minty toothpaste can take some of the itch out of a bite.
* Mosrel delivers a small electric charge and is effective for bites from mozzies, horseflies, jellyfish and fleas.
* About 30 people die every year as a result of jellyfish stings, but only six species are deadly and the risk is low.
* If you are stung, remove any remaining tentacle fragments from the area and immerse in hot water.
* Never put fresh water, alcoholic solutions or sand on the wound - it will cause a massive discharge of stingers. And do not urinate on the bite; this mythical cure is exactly that - a myth.
BEES AND WASPS
* Speed is of the essence, so try to scrape the stinger off with your finger.
* For both bee and wasp stings, apply ice or a wet cloth, elevate the affected body part and take an antihistamine tablet.
* For a natural remedy, try applying papaya to the sting.
Packing your holiday luggage is always a nightmare, given the weight restrictions and extra costs imposed by some airlines, but it is worth leaving some room for a few health essentials.
Remember that much of what you need will probably be available at your destination, but Dr Wilson-Howarth recommends taking the following, depending on where you're going.
Anti-malarial tablets (for destinations including South-east Asia, South American and parts of Africa)
Insect repellent (sticks and roll-ons are easiest to use)
Sunscreen and lipscreen
Soluble aspirin or paracetamol
Stronger, codeine-based painkillers
Sore throat pastilles
Vaseline or other heavy moisturiser
Crêpe bandage and safety pin
Mouth ulcer gel
Bugs, Bites and Bowels by Dr Jane Wilson-Howarth is published by Cadogan Guides (£9.99)Reuse content