Hi Eva.
From what I’ve read, the serious side effects are generally after years of use and particularly at higher doses. The significantly increased risk of cancer is the one which really caught my attention.
“In postmarketing surveillance, the US Food and Drug Administration has reported the development of lung masses, thyroid cancer, and skin cancer after amiodarone therapy.”
The good news is that it is dose dependent, and the dose that your cardiologist plans to bring you down to, 200mg/day, is relatively low.
“After adjustment for age, sex, and comorbidities, the hazards ratio was 1.98 (95% CI, 1.22-3.22; P = .006) for the high tertile of cDDDs compared with the low tertile.”
The 200mg/day dosage would put you in the lower tertile for this study, in terms of cDDDs.
Getting a little more into the details: “Compared with the general population, the cancer incidence was significantly higher among patients with > 180 cDDDs (SIR, 1.28; P = .046), but not among those with ≤ 180 cDDDs.”
By my calculations, your daily dose of 200mg would put you at 73 cDDDs. So, the findings from this study would suggest that your risk would be the same as the general population, at your relatively low dose.
https://acsjournals.onlinelibrary.wiley.com/doi/full/10.1002/cncr.27881
There are many other side effects associated with long term amiodarone use. The study below discusses the more well known ones. The good news is that the risks are smaller with lower doses such as yours.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4164718/