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:
Fosamprenavir and saquinavir may inhibit the metabolism of your antiarrhythmic.
What might happen:
The amount of antiarrhythmic in your blood may increase and cause life-threatening changes to your heart rate.
What you should do about this interaction:
Contact your healthcare professionals (e.g. doctor or pharmacist) right away about taking these medicines together. Your doctor may want to perform an electrocardiogram (ECG) on you to check your heart's rhythm. Let your doctor know right away if you notice an irregular heartbeat or have any dizziness or fainting episodes.Your healthcare professionals 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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