Most of us have had trouble with one drug or another. Some drugs can cause an upset stomach or drowsiness. Some drugs can threaten our lives. Drugs put more than 2 million people into the hospital every year. Drugs cause more than 100,000 deaths every year. The number of serious drug reactions goes up every year.
Allergies to sulfa drugs (aka sulfonamides) are fairly common. Sulfonamides are used in antibiotics and other medications. (Sometimes people confuse sulfa allergies with sensitivity to sulfites – which occur naturally in wine. The two are entirely different, other than they can both cause allergic reactions.)
A drug reaction is a problem caused by a drug that you or your doctor did not expect. Any prescription or non-prescription drug can cause a problem. Reactions can occur between medications. Most drugs cause trouble by working on your body chemistry. Rarely, your immune system may react to a drug or to a chemical that your body created from that drug. This type of reaction is called a hypersensitivity reaction. Allergic drug reactions are one type of hypersensitivity reaction.
Allergic drug reactions may cause:
Skin rash or hives
Wheezing or other breathing problems
Swelling of body parts
Anaphylaxis, a life-threatening allergic reaction
Reactions can occur in any part of your body.
A “pseudoallergic” or “anaphylactoid” drug reaction looks like an allergic drug reaction, but it is not allergic. This type of reaction can happen when you take the drug for the first time. This can occur with aspirin or X-ray dye. This can also happen with other drugs.
Any person can get an allergic drug reaction to any drug. Allergic drug reactions are less common than other types of drug reactions.
For a drug allergy to happen, you must have taken the drug before. You are more likely to get an allergy to a drug that gave you a drug allergy before. You can loose a drug allergy. You might have a reaction that looks like a drug allergy, but is not a true drug allergy.
If you have a family member who had a drug allergy, then you are more likely to have an allergy to any drug. You might expose yourself to that drug without knowing it. You might eat a food that contains an antibiotic. Then you could get a drug allergy to that antibiotic, if you take the antibiotic for an infection.
You are more likely to have a medication allergy if you get the drug through your veins. When you take a drug through your veins, the drug goes immediately into your blood system. The higher the amount of the drug in your blood system, the more likely you will have an allergic drug reaction to it. Less often, you can get a drug allergy from swallowing the drug. The more often you take a drug, the more likely you will have a drug allergy to it.
Diagnosing drug allergies
Drug reactions can be hard to diagnose. They can look like other diseases. Many of the drug reactions are known. Others may not have been identified yet.
It is important to figure out if the reaction you suffered is allergic or not allergic. Your doctor may ask you to see an allergist.
When you visit an allergist, you can help if you take with you the following information:
When did you take the drug
When did you stop the drug
When did you problem begin
What happened to you
How long did your problem last
What other prescription drugs did you take
What other non-prescription drugs
What health foods did you take
What herbs did you take
What minerals did you take
What are the exact names
What treatments did you get for the reaction
You should bring with you:
Your usual medicines
Your other drug reactions
Your medical and surgical problems
Problems that run in your family
Bring the exact name for all of your drugs. If you can, bring the suspected drug with you. This will help the allergist recommend different drugs, if you need them.
Dr. Zachary will give you a physical examination and will look for problems that are part of the drug reaction. She will also look for non-allergic reasons for the reaction.
Skin tests are available for some drugs. Drug challenge tests can be helpful. For a drug challenge, you take the drug and you doctor observes your reaction. If you had a serious reaction, drug challenge can be too dangerous. Drug challenge may be the best type of testing if there is no other drug to save your life. Blood tests for some drugs are available, but they are less helpful.
Sometimes you can replace the drug with other medicines. If not, then the allergistmay offer you desensitization to the drug.
Desensitization means taking the drug in increasing amounts until you can tolerate the needed dose. This must be done in a doctor’s office or hospital to get the care you need if you have problems. Desensitization can help only if you will take the drug every day. Once you stop the drug, you may need another desensitization.
For a mild reaction, you may only have to stop the drug.
For a more serious allergic drug reaction that is not life-threatening, your Allergist may give you:
An antihistamine (to counteract the histamine released into your body during the reaction)
A non-steroidal anti-inflammatory drugor a corticosteroid (to reduce inflammation)
If you have a drug allergy:
Make sure all of your doctors know the drug you took and the drug reactions you suffered
Check with your doctor about related drugs that you must avoid
Check with your doctor about drugs that you can take, if needed wear an emergency medical alert bracelet or necklace, with the offending drug engraved