Some manufacturers are selling essiac in tea bag packages. It is very hard for you to determine how old the herbs are in the tea bags. You must know the age of the herbs before making the tea. Some manufacturers are also using fillers such as cellulose in the tea bags to make up for the lack of the correct herbs. Medicinal herbs can not be any more than 6 months old.
Several variables play into the outcome of an excellent tea.
The quality of the herbs is the biggest player. In some of the essiac blends being sold in powdered form for brewing at home, the herbs are as old as 5 years from harvest. Everyone should ask these questions. Medicinal herbs should never be stored together for long term storage. The herbs should be kept apart until the time of brewing to ensure no degradation between the herbs has occurred.