The invention relates to a particulate composition comprising: c) a particulate source of stannous chloride； d) and silicon dioxide (also referred to as hydrated silica or silica). The invention further relates to a method for improving the flowability of particulate stannous chloride by admixing silica with it. The composition of the invention has been found to give improved flow properties to stannous chloride when compared to the absence of an anti-caking agent, as assessed via methods of powder characterisation detailed in the European Pharmacopoeia.
