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Iron Supplement (Oral)

Ferrous Sulphate

Brand names: Feospan, Ironorm

Ferrous sulphate is an oral iron salt used to treat iron-deficiency anaemia and, where indicated, to prevent iron deficiency.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

US labelling (FDA)

Reference — US labelling, may differ from UK

Adults and children: At the onset of symptoms, dissolve 5 pellets under the tongue 3 times a day until symptoms are relieved or as directed by a doctor.

Source: US FDA prescribing information (openFDA / DailyMed), label dated 2025-07-21. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.

Clinical monograph

How it works

It supplies elemental iron for absorption in the duodenum, replenishing iron stores and supporting haemoglobin synthesis and erythropoiesis.

Prescribing in practice

  • Iron overdose is dangerous, particularly to young children — keep it well out of their reach.
  • Gastrointestinal upset (nausea, abdominal discomfort, constipation and black stools) is common; absorption is better on an empty stomach but it may be taken with food if not tolerated.
  • Separate it from levothyroxine, some antibiotics (such as tetracyclines and quinolones) and calcium, as iron reduces their absorption.

Monitoring

Recheck haemoglobin and other red-cell indices to confirm a response, and continue treatment for a period after the haemoglobin normalises to rebuild iron stores.

Counselling the patient

  • Keep this medicine out of the sight and reach of children — an overdose of iron is very harmful to them.
  • Your stools may turn black, which is harmless; taking it with a little food can help if it upsets your stomach.
  • Do not take it at the same time as indigestion remedies, calcium, your thyroid tablet or certain antibiotics — leave a gap between them.

Evidence & guidelines

Standard first-line oral iron replacement in NICE guidance on iron-deficiency anaemia.

Reference: NICE NG24; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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