I understand your concern.
Ferritin is a form of iron storage, but it tends to go up during times of illness or inflammation. As he is suffering from recurrent infection for last few weeks so his doctor may order other tests (such as CRP or ESR) to evaluate for the underlying cause of inflammation/infection.
High ferritin could be due to excess iron consumption orally (too much non veg, iron fortified cereals, etc.) and even due to megaloblastic anemia (B 12 deficiency).
Rarely, people have a genetic problem where their body absorbs too much iron (known as hemachromatosis). Very high iron and ferritin levels can be a sign of this.
Avoid iron fortified foods (such as cereals), red meats, liver, seafood, vitamin C and alcohol.
There is nothing you can personally do to bring this level down until you know why it is up.
I would return to your doctor for further evaluation and management.
Hope this helps.
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