This is a decision you and your doctor will make. Although there are no studies on birth defects in humans, problems have not been reported. Some studies in animals have shown that aminophylline, oxtriphylline, and theophylline can cause birth defects when given in doses many times the human dose. Because your ability to clear theophylline from your body may decrease later in pregnancy, your doctor may want to take blood samples during your pregnancy to measure the amount of medicine in the blood. This will help your doctor decide whether the dose of this medicine should be changed.
Theophylline crosses the placenta.
Use of aminophylline, oxtriphylline, or theophylline during pregnancy may cause unwanted effects such as fast heartbeat, irritability, jitteriness, or vomiting in the newborn infant if the amount of medicine in your blood is too high. If the amount of theophylline in the blood is too high, side effects are more likely to occur. Your doctor may want to take blood samples to determine whether a dose change is needed. If the amount of theophylline is too high, side effects are more likely to occur. Your doctor may want to take blood samples to determine whether a dose change is needed.