What is a serious potential adverse effect of prolonged nitrofurantoin use?

Prolonged use of nitrofurantoin has been associated with the development of pulmonary fibrosis, which is a serious adverse effect. This condition arises from chronic exposure to the drug, leading to inflammation and scarring of lung tissue. The risk of pulmonary toxicity tends to increase with long-term use, especially in older adults or those with pre-existing pulmonary conditions. Symptoms may include difficulty breathing, a chronic cough, and decreased oxygen saturation. It's important for healthcare providers to monitor patients on nitrofurantoin for any respiratory symptoms, particularly if they require long-term treatment.

Other adverse effects listed, such as liver damage, anaphylactic reactions, and hepatitis, may occur but are not as closely linked with the prolonged use of nitrofurantoin as pulmonary fibrosis is. While these conditions can arise due to various medications or hypersensitivities, the significant risk of developing pulmonary fibrosis specifically is a notable concern with extended nitrofurantoin therapy.