What is the main indication for the drug Theo-Dur?

Theo-Dur is commonly indicated for the treatment of asthma symptoms. It contains the active ingredient theophylline, which is a bronchodilator. By relaxing the muscles of the airways, it helps to open air passages in the lungs and improves airflow, making it effective for patients experiencing asthma or other pulmonary conditions such as chronic obstructive pulmonary disease (COPD).

In the context of the other options, Theo-Dur does not play a role in managing glaucoma, weight maintenance, or seizure disorders, which are treated with entirely different classes of medications. This further supports the finding that the main indication for Theo-Dur is specifically related to alleviating asthma symptoms.