Pharmakeia φαρμακεια is the Greek word for pharmacy, which is the practice and making of medication and vitamins. It also refers to the making of spell-giving potions, or alchemical potions (or elixirs) believed to have transforming powers, such as the power to extend life, boost energy, or enhance the mind. It also refers to any substance used to poison someone, to prevent or treat disease (or, for that matter, to cause it), or to gain control of someone's behavior.

Pharmakeia and its related word forms pharmakeus, pharmakon, pharmakos and pharmakoi are the words from which we get the modern English words pharmacy, pharmaceutics, pharmaceutical, pharmacist, pharmacopia, pharmacology, pharmaceuticalist and pharmaceuticalism.

The modern transliteration of pharmakeia is pharmacia. Pharmakeia and its related forms appear several times in the New Testament, including the Epistle to the Galatians and the Book of Revelation. It is frequently translated as "witchcraft" or "sorcery".

Magical pharmacia substances or potions often bind someone under a spell by evocation with and without uttered word formulas. Cosmetics, lotions and perfumes were also made by practitioners of pharmaceuticalism and by extension any lab made substance or chemical falls in the realm of pharmakeia or pharmacia. In modern times petrochemicals are used to create chemical reactions with plants to create pharmaceutical substances.
One well known example is the street drug cocaine, where coca leaves are soaked in gasoline and sulfuric acid to produce the substance cocaine. Other pharmaceuticals are made solely from petrochemicals. Today people who practice organic farming and gardening are those who reject the form of pharmakeia using chemicals which is turning to witchcraft for the success of their crops.