A 38-year-old lady presented with recurrent menorrhagia and was found to have iron deficiency anaemia. She is not a vegetarian and has no other medical illness. Treatments with iron sulphate (“FeSO4” ) 300 mg twice daily was commenced.

a) What advice (e.g. lifestyle modifications) would you recommend her regarding her FeSO4 treatment? (2 marks)

Iron chelates with a lot of food and drugs.

Do not take at the same time as tea, coffee, eggs, dairy or soy bean products, because they they can impair its absorption.

FeSO4 chelates with a lot of drugs including tetracycline, calcium, magnesium salts, thyroxine, and levodopa. So check with the pharmacist if starting any new medications.

Take the iron supplement one hour before or two hours after the interacting agent.

Iron tablets cause GI irritation and constipation or diarrhoea with danger of faecal impaction in older patients. So recommend regular exercise and at least 5 portions of fruit and vegetables a day.

Tablets must be kept out of reach of children because they are a common cause of fatal overdose.

Refs:

https://www.nhs.uk/medicines/ferrous-sulfate/

https://www.drugs.com/tips/ferrous-sulfate-patient-tips

EMC

Pharmacy case studies

Other information about iron:

• Taking overdose is a medical emergency
• FeSO4 can also be taken 200mg tds
• Take on an empty stomach, either one hour before eating or two hours after for the most optimal absorption. Take with glass of water. Absorption is still low, about 10-15%.
• Dividing the dose gives greater availability for absorption. 
• It is absorbed in the duodenum, so immediate release formulations are absorbed better then slow release ones
• Causes black stool.
• Iron causes direct irritation of GI mucosa, and can be caustic in overdose.
• Due to the risk of mouth ulcerations and tooth discolouration, tablets should not be sucked, chewed or kept in the mouth, but swallowed whole with water.

Most people begin to feel better after taking ferrous sulphate for 1 week, but may take up to 4 weeks to take effect.