Important Fer-In-Sol concentration change not well known
From the January 15, 2009 issue
Clinicians and parents need to be aware of a change made to Mead Johnson Nutritionals’ oral liquid iron supplement drops. The product, FER-IN-SOL (ferrous sulfate drops), has recently undergone a change in concentration, but we are unaware of company efforts to communicate this change to healthcare practitioners or the public.
In the past, the product contained 15 mg of iron per 0.6 mL (25 mg/mL). The enclosed dropper for measuring doses had marks at 0.3 mL for 7.5 mg of iron and 0.6 mL for 15 mg of iron. The strength was changed mid-2008 to conform to the standard concentration available in countries outside the US. The new concentration is 15 mg of iron per mL (about 40% less elemental iron per mL than the original formulation), which is mentioned on the front label panel of the carton. The enclosed dropper is now marked at 0.5 mL for a 7.5 mg dose and 1 mL for a 15 mg dose. Many practitioners are unaware of this recent change—a problem compounded by the fact that iron drops made by other manufacturers remain available in the 15 mg per 0.6 mL concentration. Also, the new concentration may not be listed on pharmacy websites and drug indexes, or even on your formulary lists. Old and new packages are identical except for a brief note about the changed concentration on the new box. The NDC number and barcode are also identical.
Because dosing errors with iron can be serious, practitioners must be aware of this change. They should verify the concentration of iron in the product being dispensed and administered, and verify the volume needed to provide the intended dose. Parents should be educated if they will be purchasing the over-the-counter product, and advised to read the concentration on the bottle to assure they are purchasing the correct strength.
Also, prescribers should write the dose in mg, and any prescription written in terms of volume alone should be verified, as parents may be using measuring devices other than the dropper that came with the bottle. Hospitals should decide upon a standard concentration for this product. Generic manufacturers told us they are not planning to change to a 15 mg/mL concentration, although such a change may occur later.