Pyrrolnitrin is primarily used as a fungicide in agricultural and pharmaceutical applications. It effectively controls a range of fungal pathogens, especially those causing diseases in crops, making it valuable in protecting plants from infections such as damping-off and root rot. Due to its ability to inhibit spore germination and mycelial growth, it is used in seed treatment and soil application to enhance crop yield. In dermatology, pyrrolnitrin has been formulated into topical antifungal agents to treat skin infections caused by filamentous fungi, including certain types of dermatophytes. Its selective activity and low toxicity to mammals make it suitable for use in both crop protection and human medicine. Additionally, it serves as a lead compound in the development of new antifungal agents.