★★★★★
For your remedy, buy cinnamon (preferably ceylon cinnamon) powder, ginger powder or grated fresh ginger, black pepper powder, cardamom pods or powder (if available; but cinnamon, ginger and black pepper you should be able to get). Pour water into a boiling pot and add a big pinch of each of these spices into it, and boil for 10-15 minutes. You can use milk instead of water if you do not like the taste. Take this tea three times a day. Also, buy cayenne pepper tablets and take them or just make sure you eat something hot every day.
All of these mentioned spices are very warming, liquefy the mucous and remove obstructions in the respiratory channel. They improve blood circulation to the lungs. Cinnamon, particularly, expectorates mucus adhered to the bronchial tubes. The liquefying quality of cinnamon can be observed when you make a tea out of cinnamon powder and see that a thick, sluggish substance has formed at the bottom of the cup.
Prednisone suppresses the immune system and makes you more vulnerable to infections, and you wrote you developed a gum infection.
I hope you get better, I also used to struggle with mucus.