Displaying 4 results of Drotaverine Impurities Drotaverine is a medication used to treat smooth muscle spasms in the gastrointestinal and genitourinary tracts. However, the drug may contain impurities that can affect its efficacy and safety. Some of the potential impurities in drotaverine include related substances, residual solvents, and heavy metals. Manufacturers must closely monitor and control impurities to ensure the quality of the drug.