After receiving her masters degree, Brown began work as a research chemist at CIBA Pharmaceutical Company, where she was involved in research programs for drug development targeting tuberculosis and coccidiosis. She moved to Merck in 1969, where she co-authored 15 publications, obtained one patent and contributed to 5 others. Browns work focused on synthesizing novel medicinal compounds. She worked to develop the compound cilastatin sodium. Cilastatin is an inhibitor of renal dehydropeptidase. Since the antibiotic, imipenem, is one such antibiotic that is hydrolyzed by dehydropeptidase, cilastatin is used in combination with imipenem to prevent its metabolism. This combination creates the antibiotic Primaxin (imipenem/cilastatin), which is used to treat severe internal infections, as well as diseases caused by flesh-eating bacteria and some types of pneumonia. In order to succeed in industry, she believed that one needed to be an effective communicator, be able to work on a team, and have a strong scientific education in an ever-changing field.