A Medical Letter subscriber was surprised to discover that a new Citracal product contained not only calcium citrate, but also calcium carbonate. Citracal Plus Bone Density Builder actually contains more calcium carbonate per tablet than calcium citrate (240 mg vs. 60 mg). Another Citracal product, Citracal Plus Heart Health, also contains more calcium carbonate than calcium citrate. Many clinicians prefer calcium citrate because it can be taken with or without food, while calcium carbonate must be taken with food for optimal absorption. Other familiar over-the-counter (OTC) names also contain some surprises among their ingredients, as shown in the table below.

Many well-known brand-name OTC products no longer contain only or necessarily any of their original ingredients.