Poisonous Potions are potions made to harm the consumer, though not all are actually poisonous. Some may just be dangerous to the drinker or weaken them.
Draught of Despair[]
The Drink of Despair is a mysterious potion which induces fear, delirium, and extreme thirst. The drink cannot be penetrated by hand, vanished, parted, scooped up, siphoned away, Transfigured, Charmed, or made to change its nature in any way. It can only be drained away by drinking.
Fatiguing Fusion[]
A potion used to induce fatigue. Just inhaling the fumes is enough to feel the potions effects.
Forgetfulness Potion[]
A simple potion that is taught to first years. This potion causes temporary forgetfulness for the drinker, though the amount of memory loss is unpredictable.
Privativus Septum[]
The privativus septum potion, otherwise known as the negative seven potion, takes on a green-yellowish color when completed. The potion is highly acidic and applies acidic properties to other substances(mainly liquids), though curiously, this potion has been known to neutralize and be neutralized by poisons and venom of equal strength.