Laudanum is a tincture of opium containing approximately 10% powdered opium by weight. Laudanum is prepared by dissolving extracts from the opium poppy in alcohol (ethanol).

A tincture is typically an extract of plant or animal material dissolved in ethanol. Solvent concentrations of 25–60% are common, but may run as high as 90%. In chemistry, a tincture is a solution that has ethanol as its solvent. In herbal medicine, alcoholic tinctures are made with various ethanol concentrations, which should be at least 20% alcohol for preservation purposes.