The potency of Shakespeare's potions

It's Shakespeare's 450th birthday. In a feature article for the BBC's Future, Claudia Hammond looks at whether the poisons mentioned in William Shakespeare's plays, such as Hamlet, Romeo and Juliet and A Midsummer Night's Dream, could actually work.

Hammond writes:

There’s little doubt that each of these botanical interventions provided good plot devices for William Shakespeare. What has been the subject of debate, however, is which specific substances the playwright was referring to, and whether they would have had the desired effect. Can the 400-or-so years of science since the Bard wrote these plays provide any clues or answers? Is it really possible to pour poison into the ear of a sleeping person without waking them up? Can a drug make you fall in love with someone you’d not otherwise consider attractive? And is there a substance which can make you appear dead without causing you harm?