Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have:
fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness (like you might pass out);
vomiting and diarrhea;
confusion, ringing in your ears, hearing loss;
severe eye redness, vision problems, increased sensitivity to light;
wheezing, chest tightness, trouble breathing;
easy bruising, unusual bleeding;
pale or yellowed skin, stomach pain (upper right side), dark urine;
fever, chills, sore throat, mouth sores, swollen glands;
skin itching, flaking, blistering, peeling, or rash on your cheeks or arms that worsens in sunlight;
muscle or joint pain; or
dry mouth, trouble swallowing.
Common side effects may include:
chest pain, pounding heartbeats;
dizziness;
heartburn, nausea, vomiting, diarrhea;
flushing (sudden warmth, redness, or tingly feeling);
feeling weak or tired; or
pain or tenderness where the medicine was injected (may last for several weeks).
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.
 Quinidine side effects (more detail)
