Serious. These medicines may interact and cause very harmful effects. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
Quinidine may increase the blood level of the digitalis glycoside (e.g. digoxin).
What might happen:
Your blood levels of digoxin may increase causing loss of appetite, nausea, vomiting, diarrhea, headache, weakness, blurred vision, confusion, and a fast or slow or irregular heartbeat.
What you should do about this interaction:
Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together. Notify your doctor if you are experiencing nausea, vomiting, diarrhea, loss of appetite, unusual fatigue, fast or slow or irregular heartbeat, or vision changes (e.g. blurred vision or yellow/green halos around objects). You may need to have your blood level of digoxin checked, and your dose may need to be adjusted. You may be more likely to experience effects from this interaction if you have liver problems or are elderly.Your healthcare professionals (e.g. doctor or pharmacist) may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.
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