Herbal medicine has been used and developed over thousands of years and is the science of using plant substances to treat illness or health conditions. Modern allopathic (synthetic) medicines are based on the isolation of the powerful nutrients in herbals. An herbalist’s belief system surrounds the fact that nature has provided trace nutrients within the plant that balance and support the action of the more powerful active constituents and reduce side effects and promote balanced healing. When used in isolation, side effects may arise. As many species of the same herb exist or the environment in which they are grown can yield a different phytochemical profile, a consistent action of the herbal can be unpredictable. The part of the plant used (root, stem, leaf, or flower) can have different strengths of active ingredient or a completely different nutrient profile, with harvesting time also affecting potency levels. Standardized herbs can reduce the occurrence of varied potency and action. Also, a strong amplified or balancing effect can be achieved by using herbs together, thus the use of combination formulas can be advantageous.