Issues in the formulation of drugs for oral use in children: role of excipients.

An ideal oral drug for children should be effective, well tolerated, be of low cost and have good palatability, i.e. acceptable taste, after-taste and smell. Many of the drugs used for children are not available in suitable forms (such as chewable or liquid). Liquid forms may need to be prepared using appropriate excipients at the time of dispensing by the pharmacist. Modern medications are complex mixtures containing many other components besides the active ingredient. These are called 'inert ingredients', or excipients, and consist of bulk materials, flavorings, sweeteners and coloring agents. These excipients increase the bulk, add desirable color, mask the unpleasant taste and smell, and facilitate a uniform mixture of the active ingredient in the final marketed preparation. Unlike the active ingredients, excipients are not well regulated in most countries. Although mostly well tolerated, some adverse events and idiosyncratic reactions are well known for a variety of excipients. These components play a critical role, especially in liquid and chewable preparations that are mostly consumed by infants and children. This article reviews excipients commonly used in pediatric oral preparations.