The study focuses on iron deficiency that commonly occurs in adolescent girls, a condition where the body does not have enough iron to make healthy red blood cells. Participants will receive an oral tablet taken every other day that contains ferrous sulfate, marketed as Duroferon, while a matching placebo tablet will be used for comparison.
The purpose of the trial is to assess how practical and well‑tolerated the alternate‑day iron supplement is, how consistently participants can follow the dosing schedule, and how accurately the screening tool IRON-5 can identify iron deficiency.
During the study, each girl will take the assigned tablet on alternate days for several weeks and will attend a few clinic visits where blood samples are drawn to check iron levels and related nutrients. She will also complete brief questionnaires about diet, menstrual patterns, fatigue and overall well‑being. All information collected will help determine the safety and ease of use of the supplement and the performance of the screening tool.



Sweden