Answer
Seek immediate medical attention for new persistent chest pain, breathlessness, or a fast, fluttering or pounding heartbeat because these can indicate myocarditis or pericarditis.
Sources for this answer
- Nuvaxovid JN.1 dispersion for injection in pre-filled syringe — Current selected SmPCemc · Summary of Product Characteristics
- NHSNHS · NHS medicine guidance
General medicine information. Follow the instructions for your own medicine and speak to a pharmacist or clinician about your individual circumstances.