Iron Flashcards
Give the 2 main common clinical indications for the use of iron
1) Treatment of iron deficiency anaemia.
2) Prophylaxis of iron deficiency anaemia in patients with risk factors such as poor diet, malabsorption, menorrhagia, gastrectomy, haemodialysis and infants with low birth weight.
1) What is the aim of iron therapy?
2) What is iron essential for?
3) Iron is required for the synthesis of what?
1) To replenish iron stores.
2) Erythropoiesis.
3) Haem, which gives red blood cells the ability to carry option.
1) How is iron best absorbed?
2) How can absorption of iron be increased?
3) When absorbed into the blood, what is iron bound to?
1) In its ferrous state (Fe2+) in the duodenum and jejunum.
2) By stomach acid and dietary acids such as ascorbic acid (vitamin C).
3) Transferrin.
What happens to the iron once it is bound to transferrin?
Transferrin transports it either to be used in the bone marrow for erythropoiesis or to be stored as ferritin in the liver, reticuloendothelial system, bone marrow, spleen and skeletal muscle.
1) What is the most common adverse effect of oral iron salts?
2) What colour might a patient’s stools turn upon taking oral iron salts?
3) What 2 adverse effects can be caused by intravenous iron administration?
1) GI upset (nausea, epigastric pain, constipation and diarrhoea).
2) Black.
3) IV iron administration can cause injection site irritation and hypersensitivity reactions including anaphylaxis.
1) What effect might oral iron therapy have on patients with intestinal disease including IBD, diverticular disease and intestinal strictures.
2) In who should intravenous iron be used with caution in and why?
1) May exacerbate bowel symptoms in patients with these diseases.
2) In people with an atopic predisposition due to the risk of anaphylactic reaction.
1) Name 2 drugs that oral iron salts can reduce the absorption of.
2) Therefore, how long before taking oral iron should these other medications be taken?
1) Levothyroxine and bisphosphonates.
2) They should be taken at least 2 hours before oral iron is taken.
1) Who should intravenous iron be reserved for?
2) Describe the general prescription for patients requiring oral iron for treatment of iron-deficiency.
3) What is the general prescription for prophylaxis of iron deficiency anaemia?
1) Patients unable to tolerate sufficient oral iron to correct or prevent deficiency. Also used for patients with end stage renal disease, in whom it may be given with erythropoietin.
2) 100-200mg elemental iron per day. Once the haemoglobin has returned to normal, continue to take the prescription for another 3 months in order to replenish stores fully.
3) Ferrous sulphate 1-2 tablets daily.
1) How can GI side effects of oral iron be reduced?
2) How can IV iron be given?
3) How should you monitor a patient being treated with iron therapy?
1) By taking oral iron salts with food.
2) As an injection over 10 minutes or as an infusion.
3) Monitor FBC until the Hb has returned to normal. You should expect to see the Hb rise by around 20g/L per month.
1) What do people with iron deficiency often required order to investigate the cause of their anaemia?
2) How long before this procedure should oral iron be stopped and why is this?
1) A colonoscopy.
2) 7 days before the procedure because oral iron can turn stools black and sticky which is problematic for visualising the bowel during lower GI endoscopy (sticky black stools coat the colon and obscure the endoscopist’s view).
