is diltiazem 480 mg a day too much. Internet says 580 mg max

Should I start Sotalol or see if my afib can be controlled with diltiazem? I am 73 year old woman. Otherwise in pretty good health. First afib was six months ago, after a mild case of Covid 19. No heart problems before that. Noticed the problem because heart rate of 100 per minute at a dentist appointment. Primary Care Physician gave me referral to the heart rhythm program. Rhythm doctor immediately recommended cardioversion, which stopped the afib and I was back to normal but continued taking Diltiazem as prescribed.

The same day of my cardioversion that stopped the afib, my same heart rhythm doc told me I should start Amiodarone immediately after the cardioversion had gotten heart rhythm back to normal. When my family went to pick up the Amiodarone prescription, the pharmacist became alarmed and urged my family to warn me that Amiodarone can be very dangerous, harmful and I should get another doc's opinion before taking it. So I didn't take it. I told my heart rhythm doc I was afraid of the side effects. I asked doc to advise me about pros and cons. Doc would not tell me pros and cons. He would not give me written material, even a simple one page info sheet, about amiodarone.

A few months later afib returned. I asked, almost begged, for another cardioversion. My same heart rhythm doc refused to order another cardioversion unless I would start taking Sotalol immediately after the new cardioversion. I asked doc the pros and cons of Sotalol. He said it could have bad side effects, but didn't say what bad effects, and said I would stay in the hospital at least overnight to monitor side effects in case they were too dangerous. I asked heart doc for details on pros and cons of Sotalol. He said I could find lots of info on the internet. So I looked on internet. Next appointment, which was only two days ago, I told him I had looked on internet but have questions because I'm not an expert and I wanted him to advise me pros and cons of Sotalol. His response wat that I should just start Sotalol and that I should stop reading about it on the Internet. Of course that doc behavior is not acceptable. Standard with all docs is they should advise the patient of pros and cons, risks, of various medical recommendations so the patient can decide.

Meanwhile I am taking Diltiazem extended release. My same heart rhythm doc started me at 240 mg per day when I had the cardioversion six months ago (the only cardioversion I have had) when I didn't want to take the Amiodarone the heart doc had prescribed and urged me to take. Although the Diltiazem insert and online says it is extended release , my blood pressure and heart rate go down as desired for the first eight hours and then go back up -- each capsule lasts only about 8 hours -- does not last 24 hours although it claims to last 24 hours extended release.

QUESTION: Have any of you had that experience with extended release Diltiazem that it doesn't last 24 hours and actually lasts only about 8 hours? Pharmasysts told me yup that happens. Pharmasysts told me it's not only Diltiazem but other extended release meds do not always last as long as the manufacturer claims. But my heart rhythm doc is skeptical that it only lasts 8 hours but he prescribed 120 mg diltiazem for me to take 240 in the morning and 120 mg at night. That does not work. Both of them wear off after 8 hours.

QUESTION: Based on your experiences with your doctors and diltiazem, has your doc advised that it's ok to take 480 mg diltiazem daily, such as in three increments: 240 mg in the morning, 120 mg eight hours later, and 120 mg another eight hours later. That's what I have done this last week and it works to keep my heart rate and blood pressure down to acceptable numbers. My heart rhythm Doc said that was ok for a few days but to stop 480 per day because 480 mg was too much. I asked why, when many articles in medical reports on Internet say the maximum dose daily is 580 mg. He just said no. He said 480 would be toxic. By the way, I am a large person -- not obese but 5 feet 8 inches and about 20 pounds overweight. So, I'd like to see if I can keep the bp and hr under control with diltiazem three times a day: 480 mg in morning, then 120 mg eight hours later, and 120 mg eight hours after that.

I am looking for a different doctor to get second opinion for many reasons. In his online report about my appointment with him this week in which he wanted me to start Sotalol and I said I needed him to advise me about pros and cons, in writing, before I would decide about that, and he would'not advise me about specific pros and cons. So in his online report about that he complained that I had spent a lot of time on the Internet reading distractions, and he wrote that I had refused amiodarone and Sotalol that he recommended after I had had cardioversions (yes: plural cardioversions) when the truth is I have had only one cardioversion: the one about six months ago that he ordered. So, I need to get a second opinion and change doctors. So: he write important false information about my cardioversion etc. Also at this last appointment when he was trying to talk me into agreeing to take Sotalol, he told me he didn't blame me for not wanting to take Amiodarone; he said he wouldn't want to take Amiodarone either.

QUESTION: IN the meantime, could you let me know if you have had any problems taking Diltiazem per day 480 mg or up to 580 mg per day,
QUESTION: Also: have you known whether the extended release Diltiazem last shorter than the 24 hours it's supposed to last? mine lasts 8 hours not 24 hours.
QUESTION: Have any of you taken Sotalol and what are the pros and cons for you?

Thank you very much!