What is a known side effect of Bactrim?

Bactrim, which is a combination of sulfamethoxazole and trimethoprim, is commonly used to treat bacterial infections. One notable side effect of Bactrim is crystalluria, which is the presence of crystals in the urine. This occurs because sulfamethoxazole can lead to the formation of insoluble crystals when it's concentrated in the urine, especially in cases where hydration is inadequate. The presence of these crystals can lead to renal complications if not managed properly.

Proper hydration is vital for patients taking Bactrim to dilute the urine and reduce the risk of crystalluria. This side effect emphasizes the importance of patient education about the need to maintain fluid intake while on the medication, as it can help mitigate the risk of developing crystalluria and any subsequent complications that may arise from it.