Drug Allergy Symptoms

Drug allergies may cause many different types of symptoms depending on the drug and the degree of exposure to the drug (how often you have taken it). These are the most common reactions:

• Skin reactions:
  • A measles-like rash
    
    
  • Hives-Slightly red, itchy, and raised swellings on the skin, which have an irregular shape
    
    
  • Photoallergy-Sensitivity to sunlight, an itchy and scaly rash that occurs following sun exposure
    
    
  • Erythema multiforme-Red, raised and itchy patches on the skin that sometimes look like bull's-eye targets and which may occur together with swelling of the face or tongue
    
    
• Fever
  
  
• Muscle and joint aches
  
  
• Lymph node swelling
  
  
• Inflammation of the kidney
  
  
• Unlike most allergic reactions, which occur fairly quickly after exposure to the allergen, allergic reactions to drugs tend to occur days or weeks after the first dose of the drug.
  
  
• Anaphylaxis or anaphylactic reaction-This is a serious allergic reaction that can be life threatening. A person with anaphylaxis must be treated in a hospital emergency department. Characteristics of anaphylaxis (sometimes referred to as anaphylactic shock) include:

• Skin reaction-Hives, redness/flushing, sense of warmth, itching

• Difficulty breathing-Chest tightness, wheezing, throat tightness

• Fainting-Light-headedness or loss of consciousness due to drastic decrease in blood pressure ("shock")

• Rapid or irregular heart beat

• Swelling of face, tongue, lips, throat, joints, hands, or feet

• Almost all anaphylactic reactions occur within four hours of the first dose of the drug. Most occur within one hour of taking the drug, and many occur within minutes or even seconds.