Guaifenesin is an expectorant commonly used to relieve chest congestion caused by colds, infections, or allergies. It works by thinning and loosening mucus in the airways, making it easier to cough up and clear out. This helps improve breathing and reduces discomfort associated with congestion. Guaifenesin is available in various forms, including tablets, capsules, and syrups. It is often found in over-the-counter medications, sometimes combined with other ingredients like decongestants or antihistamines. While generally safe, it is important to follow dosage instructions and consult a healthcare professional if symptoms persist.