Is it a drug allergy or just a side effect?

Medication reactions are not always an allergy.  For example, many antibiotics will lead to non-allergic side effects, such as stomach upset or yeast infections.  This is due to irritation of the stomach or killing off of "good bacteria" as well as the bad -- leading to overgrowth of yeast and other organisms that normally are kept under check.

True allergy to a medication is an immune reaction to the drug, leading to release of histamine that can cause anything from mild to severe hives, swelling of the eyelids, lips, mouth, or throat, breathing difficulty, or life-threatening anaphylaxis.  Symptoms of a drug allergy can range from mild to life-threatening.  Once a drug allergy has occurred, it is important to let your doctors know, so that this drug can be avoided as a treatment option in the future.

Think you have a Penicillin allergy?

Think you have a Penicillin allergy, but not sure?  South Bay Allergy & Asthma can allergy skin test you to Penicillin, with results the same day.  

Many adults with a vague history of developing a rash or other adverse reaction to a penicillin type antibiotic as a child may actually be unnecessarily avoiding penicillins that could be ideal for treatment of a variety of bacterial infections.   While we would not recommend trying penicillin again if there was a history of a severe reaction such as anaphylaxis, this may be an option for patients with a history of milder reactions such as a rash or itchy skin.  For those with more severe allergies to multiple antibiotics, it is possible to desensitize to a particular antibiotic if it becomes critically needed for treatment of a severe infection.