Get emergency medical help if you have any of these signs of an allergic reaction to Pyridium: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Stop using Pyridium and call your doctor at once if you have:
little or no urinating;
swelling, rapid weight gain;
confusion, loss of appetite, pain in your side or lower back;
fever, pale or yellowed skin, stomach pain, nausea and vomiting; or
blue or purple appearance of your skin.
Common Pyridium side effects may include:
headache;
dizziness; or
upset stomach.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
 Pyridium side effects (more detail)
