Urticaria (Nettle rash or Hives) is a complaint which manifests itself in the skin, but has its real origin in the intestines. Some poison is taken into the system, and it makes its way into the skin, giving rise to blisters or weals all over the body.
As the names implies, the blisters resemble the marks produced by a sting from nettles. They may appear on the hands or face first, but generally come out all over the body.
Fish which is not quite fresh is by far the commonest cause of urticaria. You should be careful how you eat your fish. Shellfish, especially mussels, are not infrequently found guilty of producing urticaria, and also of food poisoning.
Urticaria attacks individuals in curious, inexplicable ways. Some people always have a rash after drinking champagne; others after salmon and so on through a long list of individual peculiarities.
It is easy to avoid the particular drink or article of diet that is followed by the undesirable results. For an ordinary case of urticaria, the treatment is made obvious by the cause – a poison is in the intestines, so it must be got rid of as soon as possible.
Take a dose of salts or castor oil, and be content with invalid diet for 24 hours. The rash will clear up of its own accord when the poison has been eliminated. The most soothing applications are topical lotions in form of calamine lotion, menthol with aqueous cream, and crotamiton lotion.