Answer
Covonia Sore Throat Menthol Flavour Spray has a stated shelf life of three years.
Sources for this answer
- Covonia Sore Throat 0.2%/0.05%w/v Oromucosal Spray Menthol FlavourThornton & Ross Ltd · emc · SmPC §6.3 Shelf life · Version 9Document updated
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