Cyclodextrin sulfates are cyclodextrin derivatives in which a majority of their hydroxyl groups are sulfated and have been shown to possess potentially important biological activities similar and sometimes superior to those of heparin. Because both cyclodextrin rims are surrounded by negatively charged groups, cyclodextrin sulfates interact with positively charged drug molecules such as chlorpromazine and gentamicin. Recent interaction studies of cyclodextrin sulfates indicated that both hydrophobic and electrostatic interactions take part in the complexation.