Skip to main content

How long does it take for Injectafer to work, when will I feel better?

Medically reviewed by Melisa Puckey, BPharm. Last updated on May 25, 2021.

Official answer


Injectafer infusions work rapidly and effectively to correct iron levels and some people start to feel an improvement in their symptoms within a week. It takes 2 to 3 weeks for the anaemia to be corrected and then you should have better concentration, more energy and have less breathlessness and fatigue.

Injectafer (ferric carboxymaltose injection) is used in adults to treat iron deficiency anemia.
Iron deficiency anemia is when you have a low number of red blood cells, due to not having low levels of iron.

  • Iron is needed to make hemoglobin for red blood cells, which carries oxygen around the body.
  • When iron levels are low, the body makes less hemoglobin and therefore a reduced number of red blood cells are made, causing iron deficiency anemia.
  • Once you have an Injectafer infusion your iron levels are increased to an ideal level.
  • It then takes 2 to 3 weeks for the bone marrow to use the iron to make hemoglobin, for the red blood cells and the anemia should be corrected.

Injectafer is an iron replacement infusion that can be given as a single dose or two separate doses that are separated by at least 7 days.

Bottom Line:

  • Iron deficiency anemia is caused by low iron levels
  • Injectafer corrects irons levels quickly.
  • The bone marrow take 2 to 3 weeks to use the iron to make hemoglobin for red blood cells.
  • Iron deficiency anemia symptoms start to improve within a week of having Injectafer and within 2 to 3 weeks of having correct iron levels anemia symptoms should have reduced significantly.


Related medical questions

Drug information

Related support groups