Brief Answer:
Treatment is fine, symptoms will get normal as thyroid levels get fine,

Detailed Answer:
Hello,

Thanks for writing to Health Care magic, I am Dr , Muhammad Ahmad , I have read your question closely, I understand your concern and will be helping you with your health related problem.
Hyperthroidism can cause Afib so medicine of hyperhtysoidim and afib has to be given which are Methimazole and Propranolol respectively. Afib ca cause blood clots in the heart which if fly off and get stuck in brain can cause stroke so blood thinner is also so be given so answering your question about medicine, yes this medicine is appropriate, leaving any of this can cause serious issues.

Being short of breath is understandable having Afib causes heart of beat funny and this can effect stamina of a person , and hyperthyroidism makes metabolism real fast so a person spends about 2-3 times more energy to do something compared to a normal person. These symptoms will get better as thyroid levels of your friend stay within normal range for a period of 3-4 months at least.

This being said I would like to mention here that methimazole is just the first step if that doesn't control the thyroid levels , doctors do have other options like radio iodine ablation and surgical removal of thyroid. I would suggest you to ask you friend not to panic, just get on with the treatment and hopefully when her levels stay fine for 3-4 months her symptoms will get better automatically.

I hope this answered your question, If you have more queries I am happy to answer you.
Regards.

Dr.Muhammad Ahmad

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