Brief Answer:
Inhale treatment is best for asthma.

Detailed Answer:
Thanks for your question on Health Care Magic.
I can understand your concern.
Honestly speaking, for asthma, inhaled treatment is the best treatment for asthma.
Inhaled bronchodilators (formoterol or salmeterol) and inhaled corticosteroid (budesonide or fluticasone) are the first line treatment for asthma.
So inhaled treatment is better than prednisone or magnesium sulfate.
But if want to compare between these two then prednisone is better than magnesium sulfate.
Hope I have solved your query. I will I will be happy to help you further. Wish you good health. Thanks.

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