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    Facts About Drug Allergies

    Finding out that you have an allergy to a drug can throw you. It can also bring up a lot of questions.

    The eight facts below are a good start. Talk with your doctor if you’re still not sure about things after you read them.

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    1. Anybody can be allergic to any drug. That includes prescription medications and ones you can get over the counter. Some drugs are much more likely to trigger allergic reactions, like some antibiotics, seizure medications, and some pain relievers.
    2. Symptoms can start right away or weeks later. You may start to feel things within minutes -- or even seconds -- of taking a drug. Others times, it may take days or weeks. That can make it harder for you and your doctor to figure out what caused the problem.
    3. Symptoms can be mild or severe. Drug allergies are most likely to affect your skin, causing rash or hives. They can also affect your nose, airways, ears, or lining of your stomach. For some people, they may be life-threatening.
    4. A drug allergy isn’t the same as a drug side effect. Having a bad side effect to a drug is common. It can be anything from a mild side effect (like upset stomach) to a serious problem (like damage to your heart). True drug allergies are different. When you have an allergy, your immune system is to blame. Your body mistakes something harmless -- like pollen, food, or a medicine -- for a hazard. Your immune system makes special cells and chemicals to fight it, which brings swelling and other symptoms.
    5. You can develop a drug allergy at any time. Even a drug you've been taking for years can trigger an allergic reaction.
    6. You may not have an allergic reaction the first time you take a drug. When you first take a drug, your body just becomes sensitized to it. The problem usually starts the next time you take it. By then, your body is prepared. As soon as it senses the drug in your body, it sounds the alarm and your immune system attacks.

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