Drug Allergy
- Drug Allergy Overview
- Drug Allergy Causes
- Drug Allergy Symptoms
- When to Seek Medical Care
- Exams and Tests
- Drug Allergy Treatment
- Self-Care at Home
- Medical Treatment
- Next Steps
- Follow-up
- Prevention
- Outlook
- Support Groups and Counseling
- For More Information
- Web Links
- Synonyms and Keywords
- Authors and Editors
Drug Allergy Overview
Allergic reaction is an uncommon and unwanted side effect of medication.
Several different types of allergic reactions to medications can occur. Reactions to drugs range from a mild localized rash to serious effects on vital systems. The body's response can affect many organ systems, but the skin is the organ most frequently involved.
It is important to recognize the symptoms of a drug allergy, because they can be life-threatening. Death from an allergic reaction to a medication is extremely rare, however.
An allergic reaction does not often happen the first time you take a medication. A reaction is much more likely to occur the next time you take that medication. If you have a reaction the first time, you probably were exposed to the medication before without being aware of it.
Not all adverse reactions to drugs are allergies. In fact, fewer than 10% of adverse drug reactions are allergic. Other causes of adverse reactions are interactions between two or more drugs, inability to break the drug down completely in the body (as occurs with liver or kidney damage), overdose, and irritating side effects such as nausea, vomiting, or diarrhea. If you have experienced a nonallergic drug reaction, it is important to describe it as such to medical personnel-not as an allergy. If you don't know just describe the reaction the best way that you can.
Next: Drug Allergy Causes »
| Printer-Friendly Format | | | Email to a Friend |
Allergies & Asthma
Improve treatments & prevent attacks.
From WebMD
Allergies Resources
- Allergy Issues? Get Personalized Advice
- 6 Places Germs Lurk in Your Home
- Do You Have a Mold Allergy?
Featured Centers
- 12 Ways to Prevent the Spread of Viruses
- 10 Surprising Benefits of Treating Depression
- Healthy Home: To Buy or Not to Buy Organic?
Health Solutions From Our Sponsors
Drug Allergy
Allergic Reaction Overview
An allergic reaction is the body's way of responding to an "invader." When the body senses a foreign substance, called an antigen, the immune system is triggered. The immune system normally protects the body from harmful agents such as bacteria and toxins. Its overreaction to a harmless substance (an allergen) is called a hypersensitivity reaction, or an allergic, reaction.
- Anything can be an allergen. Common dust, pollen, plants, medications, certain foods, insect venoms, animal dander, viruses, or bacteria are examples of allergens.
- Reactions may occur in one spot, such as a small skin rash or itchy eyes, or all over, as in a whole body rash.
- A reaction may include one or several symptoms.
In rare cases, an allergic reaction can be life-threatening (known as anaphylaxis). Each year in the United States, over 400 people die from anaphylactic reactions to penicillin, and ne...
Read What Your Physician is Reading on eMedicine
Drug Eruptions »
Drug eruptions can mimic a wide range of dermatoses. The morphologies are myriad and include morbilliform (most common, see Media file 1), urticarial, papulosquamous, pustular, and bullous. Medications can also cause pruritus and dysesthesia without an obvious eruption.
Featured Topics
Explore 80+ Centers
- Allergy
- Allergy Medications
- Anaphylaxis
- Antidepressants
- Anxiety
- Arthritis
- Asthma
- Baby's Health
- Back, Neck, Head Injury
- Bioterrorism, Warfare
- Blood, Lymphatic System
- Bone, Joint, Muscle
- Brain, Nervous System
- Breathing Difficulties
- Burns
- Camping
- Cancer, Tumors
- Children's Health
- Cholesterol
- Cold and Flu
- CPR, Choking
- Cuts, Scrapes, Bruises
- Dementia
- Depression
- Diabetes
- Diabetic Coma, Insulin Shock
- Digestive System
- Dislocations
- Drowning
- Drug Overdose
- Ear, Nose, Throat
- Emotional Wellness
- Endocrine System
- Environmental Injuries
- Erectile Dysfunction
- Exercise, Nutrition
- Eye, Vision
- Fainting
- Fever
- First Aid, Emergency
- First Aid Kits
- Food Poisoning
- Foreign Bodies
- Fractures, Broken Bones
- Glaucoma
- Headache
- Health, Medical
- Heartburn, GERD, Reflux
- Heart, Blood Vessels
- Heart Attack
- Hepatitis
- Immune System
- Incontinence
- Infections
- Kidneys, Urinary System
- Lung, Airway
- Medications
- Men's Health
- Mental Health, Behavior
- Multiple Sclerosis
- Nosebleeds
- Osteoporosis
- Outdoor Living
- Overexposure
- Poisoning
- Procedures
- Psoriasis
- Public Health
- Scuba Diving, Swimming
- Seizures
- Senior Health
- Shock
- Skin, Hair, Nails
- Sleep Disorders
- Social, Family Health
- Sports Injury
- Sprains, Strains
- Statins
- STDs
- Substance Abuse
- Teen Health
- Teeth, Mouth, Oral Health
- Weight Management
- Wilderness Emergencies
- Women's Health
- Wounds

