What adverse reaction should the nurse monitor for in a client taking theophylline?

Monitoring for dysrhythmias in a client taking theophylline is important due to the pharmacological effects of the medication. Theophylline is a bronchodilator that acts as a stimulant for the central nervous system and can influence heart rate and rhythm.

When theophylline levels in the body rise (especially if they exceed the therapeutic range), it can lead to side effects, including increased heart rate or abnormal heart rhythms (dysrhythmias). This is particularly concerning because dysrhythmias can result in more serious cardiovascular complications, which may necessitate immediate medical intervention.

The other potential reactions, such as headaches, hypertension, and constipation, while they may occur, do not pose the same significant immediate risk to the patient's cardiovascular status as dysrhythmias do in the context of theophylline use. Therefore, it is crucial for the nurse to closely monitor the patient for any signs of irregular heartbeats, palpitations, or changes in rhythm to ensure patient safety and effective management of the medication.