Yes. Under the Americans with Disabilities Act (ADA), an employer's duty to provide a reasonable accommodation is an ongoing one. Although some employees with diabetes may require only one reasonable accommodation, others like Gayle may need more than one. An employer must consider each request for a reasonable accommodation and determine whether it would be effective and whether providing it would pose an undue hardship.
Source: EEOC Guidance: Questions and Answers about Diabetes in the Workplace and the Americans with Disabilities Act (ADA), http://www.eeoc.gov/laws/types/diabetes.cfm, reported in Employment Practices Guide, New Developments ¶5372.