Chlorsol 50 Pharmaceutical precautions Once opened the entire contents of the 200 g sachet must be added to the required quantity of water. Seal inner bag of 2 kg sachet and keep outer container tightly closed. Contents of 2 kg sachet must be used within 7 days. Any medicated water which is not consumed within 24 hours should be discarded safely. Absorption of chlortetracycline from the alimentary tract is reduced by calcium, iron, magnesium and zinc salts. Do not store above 25°C. Store in a dry place. Unused product or waste material should be disposed of in accordance with national requirements