Hives are also known as urticaria or nettle rash. Red raised circular marks appear called weals, which resemble a dartboard bullseye. These are usually intensely itchy, and may also sting or burn. Weals appear anywhere on the body within minutes to hours of meeting an allergen or irritant. Anti-histamine tablets or cream can dampen down the reaction, and cooling agents and moisturisers can calm the itch. The weals should disappear within 24 hours, although redness or a form of bruising may persist. Hives are not contagious, and cannot be passed on.
Common culprits include medications (ibuprofen, aspirin, ramipril, enalapril and antibiotics such as penicillins), animal fur, plants or certain foods. A recent cold, other viruses, extremes of heat, cold or sweating can bring on this rash in susceptible individuals. Stinging nettles cause a classic urticaria. But more often than not, no cause is found.
If your rash is very localised and in a small area, you can use either an antihistamine cream such as 'Anthisan'. If the area of the rash is larger or spreading to other areas, it is best to use an antihistamine tablet to calm the allergic response. For skin rashes such as hives Piriton tablets (containing chlorphenamine 4mg) work very well, and a noticeable reduction in symptoms is usually achieved within 12 hours. The only downside is that the tablets need to be taken quite regularly (every four hours), and they can cause some drowsiness. If the drowsiness is a problem, then other antihistamines are available such as those containing cetirizine 10mg (found in Piriteze), or loratadine 10mg (found in Clarityn). These can be used as an alternative. The best combination in some cases may be to use a mild steroid cream such as'hydrocortisone 1% cream' to bring down the itch, and redness in the worst affected areas, and use alongside an antihistamine tablet. Be sure not to use the steroid cream on broken skin, and apply thinly no more than twice a day, unless otherwise recommended by a doctor. Overall, it is important to be aware of what triggers your hives rash, and take preventative measures to avoid them where possible, whether it is related to direct contact with skin, environmental factors, or dietary factors.
You are fit for work if you have hives.
If your rash persists beyond two days, it's worsening or spreading, or you have a recurring rash, you should book an urgent appointment with your doctor. They will discuss your symptoms and examine you. They may send you for a blood test, and refer you to a specialist, if necessary. Angioedema is a related condition, where there is swelling under the skin, there may or may not be weals, and any rash is sore when pressed but not usually itchy. The throat, tongue and skin around the eyes can swell - if you experience breathing or swallowing difficulties, call for an ambulance or attend your nearest emergency department immediately, as this may indicate a life-threatening form of angioedema.