What is the best mucus relief for COPD?

Could you please elaborate on the most effective mucus relief options for individuals suffering from Chronic Obstructive Pulmonary Disease (COPD)? Are there any over-the-counter medications or natural remedies that are particularly beneficial in managing mucus production and improving respiratory function in COPD patients? Additionally, what role does proper hydration and lifestyle modifications play in alleviating mucus symptoms associated with this condition?