Monoclonal antibodies block specific inflammatory pathways involved in the pathogenesis of asthma. These pathways are important in host defense against pathogens, and in particular, against parasites. Despite theoretical concerns about infection risk, biologics seem to have a favorable safety profile. Data from large clinical trials and postmarketing surveillance for these drugs have not shown increases in severe infections, including those from parasitic organisms. This may be due to redundancy of effector cells within the immune system. Certain drugs have special considerations and precautions, and therefore, the prescribing physician should be familiar with product recommendations and warnings.