What is the primary condition treated with decongestants?

Decongestants are primarily used to alleviate nasal congestion, which commonly occurs due to conditions such as the common cold, sinusitis, or allergies. These medications work by constricting the blood vessels in the nasal passages, leading to reduced swelling and a decrease in mucus production. This results in improved airflow and relief from the blocked nasal passages.

In the context of asthma, while some individuals may experience nasal congestion as a part of their symptoms, decongestants are not the primary treatment for asthma itself, which is more commonly managed with bronchodilators or corticosteroids. Hypertension is also not a primary indication for decongestants, as these medications can actually raise blood pressure due to their vasoconstrictive properties. Chronic pain likewise does not relate to the use of decongestants, as they do not address pain management and are focused specifically on relieving nasal congestion.

Thus, the correct choice highlights the essential role of decongestants in treating nasal problems, clarifying their purpose and function effectively.