In any event, it is safe to make this type of herbal preparation in the amount needed for an entire day. In this case, it is much preferrable to transfer the preparation into a pre-heated thermos, so as to retain its heat for as long as possible. It is usually preferrable to drink this type of preparation hot, or at least while warm. Do not make more of these types of medicinal teas ahead of time than will be needed for a day. Then make an entirely new batch after thouroughly washing the vessel.
Decoctions are much stronger medicinal teas than are infusions.
This type of preparation is usually reserved for herbs of which the roots or barks are used, since these parts of the plants are denser, and physically more complex, requiring the application of more heat over time to withdraw the medicinal constituents from an herb. To make an decoction, use 1 teaspoon of the herb for each cup of tea. Some herbs require up to 30 minutes of boiling to allow the water to withdraw as much of the medicinal constituents as possible. The use of metal or porcelain teaballs with few tiny holes is NOT acceptable for making a medicinal teas. This design does not allow a free flow of the water to constantly remove the medicinal constituents from the herb.