Biguanide (/baɪˈɡwɒnaɪd/) is the organic compound with the formula HN(C(NH)NH2)2. It is a colorless solid that dissolves in water to give highly basic solution. These solutions slowly hydrolyse to ammonia and urea.Metformin, an asymmetric dimethylbiguanidineBuformin. A butyl derivative of biguanidine.Phenformin. A phenethylated biguanidine. Biguanide (/baɪˈɡwɒnaɪd/) is the organic compound with the formula HN(C(NH)NH2)2. It is a colorless solid that dissolves in water to give highly basic solution. These solutions slowly hydrolyse to ammonia and urea. A variety of derivatives of biguanide are used as pharmaceutical drugs. The term 'biguanidine' often refers specifically to a class of drugs that function as oral antihyperglycemic drugs used for diabetes mellitus or prediabetes treatment.