Background: Cyclodextrins (CDs) are versatile excipients with an essential role in drug delivery, as
they can form non-covalently bonded inclusion complexes (host-guest complexes) with several drugs either in
solution or in the solid state.
Methods: The main purpose of this publication was to carry out a state of the art of CDs as complexing agents in
drug carrier systems. In this way, the history, properties and pharmaceutical applications of the CDs were highlighted
with typical examples. The methods to enhance the Complexation Efficiency (CE) and the CDs applications
in solid dosage forms were emphasized in more detail.
Results: The main advantages of using these cyclic oligosaccharides are as follows: (1) to enhance solubility/
dissolution/ bioavailability of poorly soluble drugs; (2) to enhance drug stability; (3) to modify the drug release
site and/or time profile; and (4) to reduce drug side effects (for example, gastric or ocular irritation). These compounds
present favorable toxicological profile for human use and therefore there are various medicines containing
CDs approved by regulatory authorities worldwide. On the other hand, the major drawback of CDs is the increase
in formulation bulk, once the CE is, in general, very low. This aspect is particularly relevant in solid dosage forms
and limits the use of CDs to potent drugs.
Conclusion: CDs have great potential as drug carriers in Pharmaceutical Technology and can be used by the
formulator in order to improve the drug properties such as solubility, bioavailability and stability. Additionally,
recent studies have shown that these compounds can be applied as active pharmaceutical ingredients.