Should Iron Supplementation Be Stopped?
Yes, iron supplementation should be stopped immediately in this patient with a ferritin of 592 ng/mL, as this level indicates adequate to excessive iron stores and continuing therapy risks iron overload without additional benefit.
Analysis of Laboratory Values
Your patient's iron parameters reveal:
- Ferritin 592 ng/mL: Well above the minimum threshold of 100 ng/mL needed for adequate iron stores 1
- Transferrin saturation 43%: Above the 20% minimum target and approaching the upper safety threshold of 50% 1
- Hemoglobin 12.9 g/dL: Normal, indicating no anemia requiring treatment
- MCV 97.9 fL: Normal to slightly elevated, ruling out microcytic iron deficiency
- TIBC 186 mg/dL: Low-normal, consistent with adequate iron availability
Evidence-Based Stopping Criteria
The patient meets multiple criteria for discontinuing iron supplementation:
- Ferritin >100 ng/mL confirms adequate iron stores have been achieved 1, 2
- Transferrin saturation >20% indicates sufficient iron availability for erythropoiesis 1, 2
- Normal hemoglobin eliminates the indication for continued supplementation 2
Safety Concerns with Continued Therapy
Continuing iron at this ferritin level poses unnecessary risks:
- Guidelines recommend withholding iron when ferritin exceeds 800 ng/mL to prevent iron overload 1
- Your patient's ferritin of 592 ng/mL is already approaching concerning levels 1
- Recent evidence suggests ferritin targets should be lowered, with iron overload risk beginning at ferritin >290 ng/mL in some populations 1
- Transferrin saturation should not be chronically maintained above 50%, and your patient is at 43% 1
Clinical Context
The low TIBC (186 mg/dL) deserves consideration:
- While low TIBC can indicate inflammation or chronic disease, it does not justify continuing iron when ferritin is elevated 1, 3
- In the presence of high ferritin and adequate transferrin saturation, low TIBC reflects iron sufficiency rather than deficiency 4
- Ferritin remains the most reliable indicator of iron stores even in inflammatory states, and 592 ng/mL is definitively elevated 1, 5
Monitoring After Discontinuation
After stopping iron supplementation:
- Recheck iron studies (ferritin, transferrin saturation) in 3 months 1, 2
- Resume iron only if ferritin falls below 100 ng/mL or transferrin saturation drops below 20% 1, 2
- Continue monitoring hemoglobin to ensure it remains stable 2
Common Pitfall to Avoid
Do not continue iron simply because the patient was previously deficient. The goal of iron therapy is to replenish stores and support erythropoiesis, not to achieve arbitrarily high ferritin levels 1. Once ferritin exceeds 100 ng/mL with adequate transferrin saturation and normal hemoglobin, the therapeutic goal has been achieved and continuation risks harm without benefit 1, 2.