Brief Answer:
Adverse interaction possible, monitor closely

Detailed Answer:
Hello,

Welcome to HCM and thank you for the query.
I understand your concern.
There is interaction between these medicines as follows.
Amiodarone increases the blood level of Diltiazem by competition for the kidney clearance. This can produce deleterious effect on the heart by decreasing the heart rate (bradycaria), more so because Metoprolol also decreases heart rate.
The interaction between amiodarone and metoprolol can also produce bradycardia especially if there is a suspicion of sinus node dysfunction. Metoprolol and diltiazem both reduce blood pressure and can lead to hypotension.
So when you are on these medicines, the blood pressure and heart rate have to be monitored closely.
Take Care
Dr Noble Zachariah

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