Practical prescribing: management of anaemia

Iron deficiency anaemia is a relatively common condition affecting up to 5% of men and postmenopausal women (Goddard et al, 2011). It has a higher prevalence in women of childbearing age due to menstrual losses. Other than blood loss, there are common causative, or aggravating factors, which include poor dietary intake, medications and difficulty absorbing iron (Shokrgozar and Golafshan, 2019).

Fortunately, in many cases oral treatment with iron supplements can successfully treat the condition. However, humans have difficulty absorbing iron from non-haem sources so pharmacological doses of iron salts (which are non-haem) can seem relatively high compared to recommended daily intakes.

A common dose for treating iron deficiency anaemia in adults is ferrous sulfate 200 mg three times daily (Joint Formulary Committee, 2019).

To the nearest whole milligram, how many moles of elemental iron are there in each 200 mg ferrous sulfate tablet?