How can I treat chronic sinus flare ups that don't let me breath?

Maximal medical tx. "chronic sinusitis" is an episode of sinusitis that has been present for > three months. When i see patients with "chronic sinusitis, " i will treat them with a minimum of three weeks of antibiotics (augmentin), oral steroids (medrol dose pak), and nasal steroids (nasonex). I usually follow this with a ct of the sinuses. I do not use decongestants. This thickens secretions and may worsen symptoms.
Abx with decongest. I would consult your primary care doctor. But you may need a course of antibiotics with a decongestant.