Do not freeze. • A cartridge in use will keep for 28 days in refrigerator. • If for some reason you cannot store your Preotact pen (with the inserted cartridge) in a refrigerator for a number of days, it can be stored outside the refrigerator below 25°C - BUT ONLY FOR A TOTAL OF 7 DAYS during the 28-day use period. • If the Preotact solution in the cartridge is more than 28 days old, or if it has not been stored correctly, throw it away, even if the cartridge is not completely empty. • If the Preotact solution becomes cloudy or coloured throw the cartridge away.