Answer
Theophylline levels vary considerably between people, and the margin between an effective concentration and toxicity is narrow.
Sources for this answer
- Aminophylline 25 mg/ml solution for injection/infusion — Current selected SmPCemc · Summary of Product Characteristics
- NHS Specialist Pharmacy ServiceNHS Specialist Pharmacy Service · NHS medicine guidance
General medicine information. Follow the instructions for your own medicine and speak to a pharmacist or clinician about your individual circumstances.