Therapeutic serum level for methylxanthines is typically within which range?

Therapeutic serum level for methylxanthines is typically within which range?

• A. 1-5
• B. 25-30
• C. 50-60
• D. 10-20

Answer: (D)

Methylxanthines have a narrow therapeutic window, so keeping the serum level within a specific range is key to balancing effectiveness with safety. For theophylline, the typical therapeutic range is about 10 to 20 micrograms per milliliter. Staying in this range provides bronchodilation with a lower risk of toxicity. Levels around 25 to 30 mcg/mL or higher raise the chance of adverse effects such as tachycardia, arrhythmias, and seizures, while levels well below, like 1 to 5 mcg/mL, are usually subtherapeutic. Very high levels, such as 50 to 60 mcg/mL, are dangerous.

Methylxanthines have a narrow therapeutic window, so keeping the serum level within a specific range is key to balancing effectiveness with safety. For theophylline, the typical therapeutic range is about 10 to 20 micrograms per milliliter. Staying in this range provides bronchodilation with a lower risk of toxicity. Levels around 25 to 30 mcg/mL or higher raise the chance of adverse effects such as tachycardia, arrhythmias, and seizures, while levels well below, like 1 to 5 mcg/mL, are usually subtherapeutic. Very high levels, such as 50 to 60 mcg/mL, are dangerous.