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Iron supplement (treatment for iron-deficiency anaemia)

Ferrous Sulfate: uses, side effects & precautions

Also known as Iron tablets, Feospan, Ferrous Sulphate, ferrous fumarate (related), ferrous gluconate (related), Slow-Fe.

Ces informations sont fournies à titre indicatif uniquement et ne constituent pas un avis médical. Consultez toujours un professionnel de santé qualifié pour toute préoccupation médicale personnelle. En cas d'urgence, appelez votre numéro d'urgence local.

What it is used for

  • Iron-deficiency anaemia, including from heavy periods or pregnancy
  • Preventing iron deficiency in pregnancy or when iron needs are high (when advised)

How it works

It replaces iron the body needs to make haemoglobin, the part of red blood cells that carries oxygen, correcting or preventing iron-deficiency anaemia.

How it is taken

Taken as a tablet or liquid, often once daily or as advised, sometimes with vitamin C-rich food or drink to aid absorption. Take it exactly as your doctor, pharmacist, or label directs, and keep iron well out of reach of children.

No doses here on purpose. The right strength and schedule depend on you — only a doctor or pharmacist should set them. Always follow your prescription and the label.

Common side effects

  • Constipation
  • Stomach upset or pain
  • Nausea
  • Diarrhoea
  • Dark or black stools (harmless)
  • Temporary staining of teeth with liquid forms

Serious effects — get help

  • Severe stomach pain or vomiting
  • Signs of a serious allergic reaction
  • In children, accidental overdose is dangerous and needs emergency care

If a reaction is severe — for example trouble breathing, swelling of the face or throat, or collapse — go to the nearest emergency room now or call your local emergency number. Do not wait for an online consultation.

Interactions to watch

  • Some antibiotics (tetracyclines and quinolones)
  • Levothyroxine and some other medicines (separate the timing)
  • Antacids and indigestion remedies
  • Calcium supplements
  • Tea and coffee taken at the same time can reduce absorption

Who should take care

  • Keep iron strictly away from children, as overdose can be life-threatening
  • Take it apart from certain medicines and from tea, coffee, or dairy where advised
  • Tell your clinician if you have bowel disease or repeated stomach upset
  • Have your iron levels rechecked as advised rather than continuing indefinitely

Frequently asked questions

Why are my stools black?
Dark or black stools are a normal, harmless effect of iron. However, tell your clinician if stools are sticky and tar-like or you feel unwell, as this can signal bleeding.
How can I reduce constipation?
Drink plenty of fluids, eat fibre, and ask your pharmacist about options. Some forms or schedules are gentler on the stomach.
What helps iron absorb better?
Vitamin C, such as a glass of orange juice, can help, while tea, coffee, dairy, and antacids near the dose reduce absorption.
How long do I take it?
Often for several months to rebuild iron stores, with blood tests to guide when to stop. Follow your clinician's advice.
Is Ferrous Sulfate safe to take?
For most people it is safe when taken exactly as a doctor or pharmacist advises and as printed on the label. Tell your clinician about your other medicines and health conditions, and seek urgent care for any serious reaction.

Related conditions

Related medicines

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