No harmful interaction between Livosin DS Herbal Liver Tonic and metformin has been documented, but caution is advised. Herbal formulations can affect liver function, and metformin relies on the liver and kidneys for proper clearance. Therefore, using Livosin DS along with metformin should be done only under medical supervision. Your doctor will assess your diabetic condition and overall health and decide whether the potential benefits outweigh the risks.