Abstract: Recently, the effects of timing drug administration to correspond to biological rhythms in fighting certain diseases have come under study by researchers. This has led to the development of chronotherapeutic medicines which are maximally effective at different points in our circadian cycle. The paper reviews some of the important features of chronotherapeutic medicines and their contribution to improvement in therapy.
We live today in a world of drugs. It has become common for people to take drugs for years, even decades, to reduce risks of disease and increase life span. With many drugs, the basic goal of a treatment is to supply the appropriate amount of drug to the proper site in the body. The design of proper dosage forms is an important element in accomplishing this goal. Thus dosage forms of drugs (customarily known as medicines such as tablet, capsule, injection etc.) emphasize the complex nature of delivering drugs in an optimal fashion.
By no means it was not always so. Before the end of the 19th century, medicines were concocted with a mixture of empiricism and hope. The technology of making dosage form of drugs was simple and crude. The modern era of dosage form techniques can be marked from WWII (1934-44). Stabilizing the dosage form and ensuring its accurate dose were the basis in the preparation of dosage form.
In the second half of the 20th century, things changed remarkably as technological advancements in greater in-depth understanding of physicochemical behavior of drugs have resulted new techniques of drug delivery. In the early 1950s SmithKline and French (SKF) introduced spansule dosage form. It was a major breakthrough in achieving a controlled measure of the therapeutic effect. It quickly released the required initial dose in the body and then slowly and gradually released many small doses to maintain a therapeutic level lasting up to 12 hours, providing all-day or all-night therapy with single dose. These types of dosage forms were developed with the aim of sustaining drug levels and hence extended period of time. The progressively more important role of the controlling drug levels in the body with precision marked the beginning of modern era of dosage for technology. Today, modern techniques are capable of controlling the rate of drug release from the dosage form, sustaining the duration of a treatment and/or targeting a drug to a specific tissue or organ.