Are allergic reactions common to antibiotics?

Yes: Antibiotic allergies are very common.

Yes: Statistically the penicillin family of antibiotics trigger the most reactions because they are so universally used. Penicillin testing is widely available by allergists and is recommended to avoid needlessly avoiding this inexpensive and effective family of antibiotics. But any kind of antibiotic carries with it the chance of allergy, and as a class, is one of the most common drug causing allergy.