Potential decrements in job performance are associated with a wide variety of pharmaceutical agents, including antimetabolites, antineoplastics, gout medications, biologicals, hormones, plasma fractions, and antibiotics. The number of potential employees taking these medications ranges from less than 1 in 1000 for the antineoplastics in 1 in 10 for some biologicals. Whether a particular employee will experience a medication-induced performance decrement with these medications, as well as the extent of such a decrement, is in large part a function of factors such as individuality in drug response, the employee's age and diet, and drug interactions.