The theophylline and aminophylline market is projected to grow from USD 337.5 million in 2025 to USD 411.4 million by 2035, at a CAGR of 2.0%. Chronic Obstructive Pulmonary Disease (COPD) will dominate with a 48.6% market share, while hospitals will lead the end user segment with a 55.3% share.