Starch is widely used in the pharmaceutical industry as binders, disintegrants and as diluents because it is readily available, inert, and cheap. Starch was extracted by conventional method from sweet potatoes (Ipomoea batatas) which are commonly grown in developing countries including Nigeria. The extracted starch was evaluated for its properties such as amylose/amylopectin content, pH, moisture content, loss on drying, micrometrics, and compression behavior using Kawakita and Ludde model. The starch was also evaluated for its binding effect in ethambutol tablet formulations and compared with equivalent concentration of standard maize starch as a binder in ethambutol tablet formulations. The sweet potato starch was found to have amylose content of 24.4 %, 7.8 % loss on drying and of poor flowability as indicated by Hausner’s quotient, Carr’s compressibility index and the angle of repose. The granules of ethambutol prepared by wet granulation method using the sweet potato starch compared favourably with those prepared with the standard maize starch in their micrometric properties such as Hausner’s quotient, Carr’s compressibility index, bulk and tapped densities and angle of repose. Tablets containing potato starch as binder had faster disintegration time, higher friability than those containing equivalent amount of maize starch. However, there was no significant difference in the amount drug released in the tablets prepared with sweet potato starch and those prepared with maize starch at 5%, 7.5% and 10 % binder concentrations (p < 0.05). Starch from sweet potato can therefore serve as cheaper alternative to the imported maize starch B.P.
