For those of you who are cautious with their caffeine intake, there's a natural way to decaffeinate any tea.   The simplest way is to use an infuser to steep the tea in freshly boiled water for about 30 seconds; since caffeine is very water soluble, it will be quickly released into the water in this time frame.  Next, toss out the water, which will contain the dissolved caffeine, and steep the tea leaves a second time by pouring freshly boiled water over it - this time, the tea will contain only trace amounts of caffeine.

Herbal teas such as Chamomile, Peppermint and Rooibos, are naturally caffeine free so there is no need to decaffeinate these teas.  It is not recommended to try this process with tea bags purchased from the supermarket - these teas are very mild-flavored compared to some higher quality loose leaf teas, and will lose their flavor very quickly.  Loose leaf green, and white teas, however, can easily provide a flavorful 2nd and third cup of tea. The great benefit with re-steeping green and white tea, is that with each steeping (up to 3), the flavonoid content (natural antioxidants in tea) actually increases as the tea leaves break down.

This decaffeination process only removes about 70 to 85% of the caffeine from the tea - comparatively, commercial processes remove almost 95% of the caffeine, but often involve harmful chemicals in the process.  If you have a strong reaction to caffeine, then it would be advisable to stick with naturally caffeine free herbal teas.