Hypoglycemia was a condition in which a person has lower than normal blood sugar levels.
Lee, a woman who worked at the Sanctuary District in San Francisco in 2024, had hypoglycemia. She began to feel the effects of it while being held hostage in the District's offices by Biddle Coleridge, Michael Webb, and Benjamin Sisko (posing as Gabriel Bell). However, Dr. Julian Bashir, who like Sisko arrived in 2024 from 2371 due to a transporter accident, helped Lee through her ordeal and attempted to get her a candy bar to help increase her blood sugar level. (DS9: "Past Tense, Part II")
Skipping meals could also lead to low blood sugar levels, something which The Doctor warned Kes about in 2372 after she missed lunch to run an analysis for him. He apologized for it shortly afterwards, blaming his unwelcome comments on his programming. (VOY: "Parturition")