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clozapine oral

Fosphenytoin/Selected QT Prolongers

This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

Medical warning:

Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

Fosphenytoin can affect your heart's rhythm. Other drugs can have the same effect.

What might happen:

Taking fosphenytoin with other agents that can affect your heart rhythm may increase your risk of an irregular heartbeat, which may be life-threatening.

What you should do about this interaction:

Let your healthcare professionals (e.g doctor or pharmacist) know that you are taking these medications 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.

References:

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