Answer
Calcium carbonate can reduce levothyroxine absorption. Ask a pharmacist or prescriber how to separate the products appropriately.
Sources for this answer
- Calcium Carbonate 500mg Chewable Tablets — Current selected SmPCemc · Summary of Product Characteristics
- Rennie 750mg Medicated Chewing Gum — 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.