Relieves headache & fever. Thins & loosens mucus. Pain reliever and fever reducer. Some colds really work their magic; if you're not dealing with a headache, you're battling severe congestion that makes it difficult to breathe. And no cold would be complete without that 24/7 menace known as mucus. When you're fighting a cold like this, Maximum Strength Mucinex Fast-Max Severe Congestion & Headache can deliver relief. It relieves headache, clears nasal congestion and breaks up the party that mucus is having in your chest.