Breo Ellipta precautions. Certain people who are very sick or very old or who are sensitive show an exacerbation of side effect of the drug which can turn dangerous at times. So, it is very important to remember the precautions while taking the drug. Pregnancy and Breastfeeding are also special categories wherein extra care or precaution is needed when taking a drug. Few patients may have a hypersensitivity reaction to few drugs, and that can be life-threatening rarely. Penicillin hypersensitivity is one example.