Severe anaphylactoid reactions may occur with iron dextran. It is therefore recommended that it be given where there are facilities for the emergency treatment of such reactions, the Intramuscular injection is associated with local reactions, pain, and staining at the site of injection; leakage along the injection track may occur unless the proper technique is used .

Rapid intravenous use may be associated with vascular flushing and hypotension. Thrombophlebitis may occur at the site of injectionCardiovascular effects such as chest pain or tightness, myocardial infarction, hypertension, tachycardia, bradycardia, and arrhythmias may occur with either route. Rashes, urticaria, purpura, and pruritus have been reported. Other reactions include gastrointestinal disturbances, dyspnoea, and taste disturbance.

Patients may also experience delayed reactions 1 to 2 days after injection of iron dextran, such as backache, arthralgia, myalgia, chills, fever, paraesthesia, dizziness, malaise, headache, nausea, and vomiting.

Overdose of parenteral iron is unlikely to be associated with any acute manifestations. Unwarranted parenteral iron therapy will result in iron overload and excess storage of iron (haemochromatosis) in the long term. The consequences of this include liver and endocrine dysfunction and heart disease , and possibly an increased risk of infection