What are the side effects of quinidine?

Common side effects of quinidine (sulfate and gluconate forms) include: diarrhea, loss of appetite, muscle weakness, mild upset stomach, headaches, nausea, or vomiting. These side effects are not serious and only require medical attention if they do not go away or suddenly worsen. Quinidine may cause serious side effects, including allergic reactions. If you experience signs of an allergic reaction, such as swelling, hives and difficulty breathing, seek immediate medical attention. Talk to your doctor if you experience any of these rare but serious side effects: ringing in the ears, changes in vision, dizziness, fainting, rapid heartbeat, headaches, abdominal pain, chest pain or yellowing of the skin or eyes. Quinidine may cause unexpected side effects that are not described above. If you experience an unanticipated reaction while taking quinidine, talk to your doctor.

Based on information from, a free medication monitoring service, 16% of patients experience side effects while taking Quinidine. Some of the side effects reported by iGuard members include:

  • Light Sensitivity 
  • Diarrhea 
  • Headache 
Please follow up with your doctor or other healthcare provider if you are experiencing any symptoms that worsen or do not go away.

Continue Learning about Muscoloskeletal Agent

Is Synvisc a good alternative to joint replacement?
Keith Roach, MDKeith Roach, MD
Synvisc is not generally an alternative to joint replacement in people with very advanced knee osteo...
More Answers
How long does it take to get pain relief from hyaluronic acid injections?
Dr. Vonda Wright, MDDr. Vonda Wright, MD
I never guarantee my patients that they're going to see any effect from hyaluronic acid (HA) injecti...
More Answers
Can Botox affect my emotional reactions?
Scientists believe that facial expressions may influence our emotions, meaning that those whose face...
More Answers
How effective is leflunomide at treating psoriatic arthritis?
Donna Hill Howes, RNDonna Hill Howes, RN
There has been very little research on using leflunomide to treat psoriatic arthritis. Small studies...
More Answers

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.