A Derby nurse practitioner whose prolific prescribing of potent narcotics was the subject of a February story by C-HIT has surrendered her state and federal licenses to prescribe controlled substances and is the subject of an “open investigation” by the state health department, officials said Monday. Heather Alfonso, an advanced practice registered nurse (APRN) at the Comprehensive Pain & Headache Treatment Centers, LLC, in Derby, surrendered her controlled substance registration after a recent probe by the Drug Control Division of the Department of Consumer Protection, a spokeswoman for the department confirmed. “The controlled substance registration of this provider has been turned in,” said the spokeswoman, Claudette Carveth. She said the agency had no further comment. Meanwhile, William Gerrish, a spokesman for the Department of Public Health, said his agency has an ongoing investigation into Alfonso’s APRN license, which is separate from her prescribing registration.