Methylxanthines are relatively weak bronchodilators that come in tablet form.  Methylxanthines can also found in coffee, tea, and chocolate but they are not as strong as the pills your doctor would prescribe. Taken regularly, methylxanthines help relax the smooth muscle around the airways of the lungs which offers modest improvements in pulmonary function, exercise performance, and relief from breathlessness.  Adding these tablets to inhaled bronchodilator therapy may benefit some people with COPD; however, the benefits need to be weighed against the risk of serious side effects.  This medication is not one of the first COPD medications used for long term treatment as there are safer and more effective medicines available. Drug interactions are also common and it is necessary to monitor drug levels with blood tests.

Examples of Methylxanthines:

Theophylline
Aminophylline

Possible side effects:

Headache, irritability, nervousness, rapid or irregular heartbeat, insomnia, tremors, upset stomach, nausea diarrhea, seizures