1. A composition comprising non-water soluble carbohydrates, wherein at least 50% of the non-water soluble carbohydrates are carbohydrates selected from derivatives of lactose, maltose, trehalose, raffinose, glucosamine, galactosamine, lactosamine, or derivatives of disaccharides with at least two pyranose saccharide units, trisaccharides, tetrasaccharides, or mixtures thereof, and wherein the composition is a liquid before administration into the human or animal body and increases in viscosity by more than 1,000 centipoise (cP) after administration, wherein the composition is a liquid before administration and has the ability to transform into a gel-like material after administration, and wherein the composition comprises at least one active pharmaceutical ingredient which is a chemotherapeutic drug, an anti-infectious agent, or a combination thereof wherein the composition comprises at least one triglyceride in an amount of 10-50 wt % of the composition.