The blotchy rash of hives
The blotchy rash of hives can follow ingestion of almost any food, ‘but among the most common causes are shellfish, nuts, and berries. A person who is allergic to aspirin (acetylsalicylic acid) should also be wary of foods that contain natural salicylates. These include apricots, berries, grapes, raisins and other dried fruits, tea, and foods processed with vinegar. Among the other well-known triggers of hives are emotional stress; exposure to sunshine, heat, or cold (even ice cubes in drinks); and viral infections. Hives generally develop within hours after exposure to a trigger, but in unusual cases, they may appear several days later. This delayed reaction can make it difficult to identify the offending substance. Delayed reactions are most common with medications; if you develop a rash while taking any drug, report it to your doctor immediately. Medication-related rashes usually start around the head and spread progressively downward, Sometimes a drug allergy develops abruptly after months or even years of taking a medication. Always mention your sensitivity to the pharmacist and any doctor who may prescribe medications for you.
