Misc Antifungal Agents/Astemizole; Terfenadine
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:
When these two medicines are taken together, your body may not process your allergy medicine properly.
What might happen:
Your blood levels of your allergy medicine may increase and cause life-threatening effects on your heart.
What you should do about this interaction:
Contact your healthcare professionals (e.g. doctor or pharmacist) as soon as possible about taking these two medicines together. They may already be aware of this interaction and may be monitoring you for it. You may need to change to an different allergy medicine, or stop taking it while taking the antifungal medicine. Do not start, stop, or change the dosage of any medicine before checking with them first.
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