What are the Side Effects of Bactrim?

Some of the common side effects of bactrim include nausea, vomiting, GI upset, headache, allergic rash, photosensitivity, lethargy etc. Some of the serious adverse reactions of bactrim include liver injury (hepatotoxicity), kidney injury (nephrotoxicity), serious life-threatening allergic reactions, electrolyte disturbances, blood disorders etc.