“What are the natural treatments for bronchitis?”

Yes it is treatable. I treat it all the time

I like to use homeopathic cell salts for acute issues like bronchitis. Ferrum Phos 6x is good at the onset of infection and helps to boost immune defenses. Kali Mur 6x can be useful with bronchitis to help lubricate the lungs and discharge mucus. It also helps reduce lymph gland swelling and inflammation caused by the condition.

You can take 1 tablet every 15 minutes when symptoms are severe and then decrease frequency to 1 tablet, 3 times daily until symptoms resolve.