Hypervitaminosis
Hypervitaminosis is a condition of abnormally high storage levels of vitamins, which can lead to various symptoms—whether physiological, such as pain, nausea, and tachycardia, or psychological, such as confusion, hyperactivity, and irritability—and even to toxicity. Specific medical names of the different conditions are derived from the given vitamin involved: an excess of vitamin A, for example, is called hypervitaminosis A. Hypervitaminoses are primarily caused by fat-soluble vitamins (especially D and A), as these are stored by the body for longer than the water-soluble vitamins.