Decongestants work by reducing swelling and inflammation in the nasal passages, which helps open the airways and improve airflow. Herbal decongestants include eucalyptus (Eucalyptus globulus), whose essential oil is known for its vasoconstrictive properties that help clear nasal passages, and peppermint (Mentha × piperita), which contains menthol, providing a cooling sensation and helping to relieve nasal congestion. Thyme (Thymus vulgaris) and ginger (Zingiber officinale) are also often used to stimulate circulation and reduce mucus buildup.

Decongestants can be used in the form of steam inhalation, topical rubs, or teas to help relieve nasal congestion. Maintaining adequate hydration, using humidifiers, and practicing steam inhalation are also effective measures for reducing congestion and supporting respiratory comfort.