Answer
Some matrix modified-release tablets can leave an empty remnant after releasing the medicine. This does not usually mean the treatment was not absorbed.
Sources for this answer
- Eumon 40 XL Modified Release Tablets (Isosorbide Mononitrate) — Current selected SmPCemc · Summary of Product Characteristics
- Isotard XL — Current selected SmPCemc · Summary of Product Characteristics
General medicine information. Follow the instructions for your own medicine and speak to a pharmacist or clinician about your individual circumstances.