Alchemy is a Skill that appears in The Elder Scrolls V: Skyrim. It allows players to create effective potions and poisons at labs and alchemy stations. Alchemy is a science in progress; players must experiment with different combination to find the process that results in the best result.
One of 18 skills, Alchemy is the Thief's counterpart of the Mage's Enchanting and the Warriors Smithing.
All ingredients have four effects. You can learn the first effect of any ingredient by selecting it in your inventory and eating it. To learn the other effects, experiment with it.
At an Alchemy Lab, two or three ingredients can be combined in an attempt to make a potion or poison. If the ingredients share at least one effect, you succeed and will learn all of the effects that match. If none of their effects match, you fail and lose the ingredients.
When you create something, it can have both harmful and helpful properties. If the strongest property is helpful, you have a potion; if the strongest property is harmful, you have a poison.
Potions are used by consuming them. If you consume two potions with the same effect, only the most powerful effect is applied, so wait for one potion to wear off before drinking the next.
Poisons are used by applying them to your equipped weapon.