Readers have asked us to update our 2004 article on tablet splitting. Breaking drug tablets in half is a common practice, but the FDA recently advised consumers against it (FDA Consumer Health Information, July 2009). Tablet splitting may not have adverse clinical consequences and can reduce costs for both patients and institutions, but using a whole tablet is the safest way to ensure accurate dosing, and splitting tablets is not appropriate for all patients or all drugs. When it is appropriate, splitting tablets one at a time can minimize under- or overdosing.