Brief Answer: it's ok Detailed Answer: You can switch medications from one day to another if medically necessary. There is no such thing as your body getting used to a certain blood pressure medication, or requiring a slow withdrawal of the medication as with other type of medications (such as antidepressants, pain meds, etc). You were on a relatively high dose of verapamil (maximum recommended daily dose is 480mg, and you were on half of that. Metoprolol ER you should start it a lower doses as your doctor did, since you don't know how your body is going to react to it. 25mg is the lowest available dose, but you can go as high as 400mg! (but again not all at once). Metoprolol is probably going to be a better medication for you since it decreases your heart rate, hence it should definitely help with your palpitations. What i would suggest is checking your blood pressure at least 2-3 times a day until you get a to the right dosage. You have to be in close contact with your doctor in order to increase it adequately. Hope that helps

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