Severe. These medicines may interact and cause very harmful effects and are usually not taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
The cause of the interaction is not known. Amiodarone may increase the effects of quinidine.
What might happen:
Your blood levels of quinidine may increase and cause toxic effects, including a life-threatening irregular heartbeat.
What you should do about this interaction:
Let your healthcare professionals (e.g. doctor or pharmacist) know right away that you are taking these medicines together.If you experience an irregular heartbeat or any dizziness or fainting episodes, contact your doctor. Your doctor may need to adjust your dose of quinidine. This effect may be worse if you are also taking moricizine, procainamide, or disopyramide.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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