What side effects may I notice from receiving Trimethoprim?

Side effects that you should report to your doctor or health care professional as soon as possible:
-allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
-fast or irregular heartbeat, chest pain
-fever or chills, sore throat
-bluish fingernails or lips
-difficulty breathing
-redness, blistering, peeling or loosening of the skin, including inside the mouth
-unusual bleeding or bruising
-unusually weak or tired

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
-aches or pains
-changes in taste
-diarrhea
-headache
-nausea, vomiting
-stomach pain

This list may not describe all possible side effects for Trimethoprim. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.