Sponix Anti-Fungal, generic name Undecylenic Acid - topical, is used to treat fungal skin infections such as tinea pedis and itchiness. Undecylenic acid is a fatty acid that works by stopping the growth of fungi. This product should not be used to treat fungal infections of the scalp or nails. Read more articles below to understand more about the drug Sponix Anti-Fungal.