If you do not respond to the treatment prescribed for your drug allergy, it is important that you see a medical professional for re-evaluation.

There is no known way to prevent drug allergies. You can reduce your risk by taking as few medications as possible. The more exposure your body has to medications, the greater the likelihood of a drug allergy.

Always tell any new health-care provider you see about your allergies and the types of reactions you have had. Talk to your doctor about the possibility or necessity of having a portable epinephrine kit to treat severe reactions.

Do not take a drug that you have reacted to in the past. Once you have a reaction to a drug, your risk of having a more severe reaction next time increases dramatically.

Consider wearing a medical alert ID bracelet or necklace. These devices are worn on the wrist or neck and can alert medical personnel and others about the risk for an allergic reaction.

Adults might carry a card with pertinent medical information in a wallet or purse. Tell your health-care provider about any adverse reactions to medications in the past before he or she prescribes medications to you.

Tell your health-care provider about any medications, prescription or over-the-counter, that you are taking.

Most people who have mild to moderately severe allergic reactions to a drug do very well. With treatment and stopping of the drug, most people will be much better within 48-72 hours.

Most people also do well after a severe drug allergy if they are evaluated promptly by a medical professional and treatment is started. Some reactions can be life-threatening, including serum sickness and anaphylaxis. People who have these reactions generally need to be admitted to the hospital.

Generally a drug allergy is identified by signs and symptoms. Medical professionals are trained to recognize hives, swelling patterns, and rashes associated with allergic reactions.

You will be asked questions about your medical history and possible triggers of the reaction.

Blood tests and other tests are needed only under very unusual circumstances.

Always contact the health-care provider who prescribed the medication for advice.

If the symptoms are mild, such as itching and localized hives, the provider may switch you to a different type of medication, recommend that you stop the medication, or, if appropriate, prescribe antihistamines to relieve your symptoms.

If you cannot reach this provider for advice quickly, play it safe and go to a hospital emergency department.

If you are having any "systemic" symptoms such as fever or vomiting, you should stop taking the medication and be seen immediately by a medical professional.

If you are having difficulty breathing, your throat is swelling, or you are feeling faint, you may be having an anaphylactic reaction. Go immediately to a hospital emergency department. Do not attempt to drive yourself. If no one is available to drive you right away, call 911 for an ambulance. While waiting for the ambulance, start self-treatment.