What is a serious adverse reaction to theophylline?

Theophylline is a medication commonly used in the treatment of respiratory conditions such as asthma and chronic obstructive pulmonary disease (COPD) due to its bronchodilator effects. However, alongside its therapeutic benefits, it carries the risk of serious adverse reactions, one of which is arrhythmias.

Arrhythmias are irregular heartbeats that can range from benign to potentially life-threatening conditions. Theophylline can cause tachycardia (increased heart rate) and other types of arrhythmias primarily because it stimulates the central nervous system and can increase catecholamine release, which raises heart rate and can lead to disturbances in cardiac rhythm. This side effect necessitates careful monitoring of patients on theophylline, particularly those with pre-existing cardiovascular conditions.

While insomnia, nausea, and vomiting are potential side effects associated with theophylline use, they are typically considered less serious than arrhythmias and do not usually pose an immediate risk to life or require urgent intervention. Therefore, arrhythmias stand out as a significant and serious adverse reaction to theophylline therapy.