Melissa asked
Is liquid Piriton still effective if used 12 months after opening ? Thank you
Answer
Piriton is a brand name for the first-generation antihistamine chlorpheniramine. Like most first-generation antihistamines, chlorpheniramine can cause sedation and is relatively short acting, around 6 to 12 hours per dose.
Piriton syrup products should all be marked with a manufacturer expiration date, and should not be used after this date. Opening Piriton does not affect this expiration date as long as it has been stored at the recommended storage conditions:
"Do not use this medicine after the 'EXP' date shown on the pack. Store below 25°C. Protect From Light."So, depending on the expiration date, it may be safe to use Pirion 12 months after opening. Please reference the packaging of the product.