For a patient with a serum theophylline level of 16 mcg/mL, what does this indicate?

A serum theophylline level of 16 mcg/mL is considered therapeutic. The therapeutic range for theophylline generally falls between 10 to 20 mcg/mL. Within this range, the drug is effective in managing conditions like asthma or chronic obstructive pulmonary disease (COPD) without causing significant toxicity.

It's important to monitor serum theophylline levels because levels below 10 mcg/mL may fail to provide sufficient bronchodilation and symptom control, while levels above the upper threshold of 20 mcg/mL can lead to adverse effects and toxicity, which may include symptoms like nausea, palpitations, and disturbances in heart rhythm. Therefore, at 16 mcg/mL, the level is well within the safe and effective range aimed at achieving therapeutic benefits.