Varcystine 400 Injection is an antidote medication. It is used in the treatment of paracetamol overdose (when you may have taken too much paracetamol medicine). It protects your liver and helps to reduce the extent of the injury. Varcystine 400 Injection is given as an injection under the supervision of a doctor. It must be injected within 8 hours of paracetamol overdose. It can be given up to 24 hours, but medicine effective slow down when given after 24 hours of dosage overdose. Your doctor will decide how much you need to improve your symptoms. Always follow your doctor's advice while taking this medicine. The most common side effects of this medicine include rash and hives. If these bother you or appear serious, let your doctor know. There may be ways of reducing or preventing them. Before taking this medicine let your doctor know if you suffer from asthma, as close monitoring is required while taking this medicine. Your doctor should also know about all other medicines you are taking as many of these may make this medicine less effective or change the way it works. Inform your doctor if you are pregnant, planning pregnancy, or breastfeeding.