I'm sure the medical community would like to know. After all, a drug which can induce a coma for over two days followed by complete recovery would be very useful as an anaesthetic. Unfortunately, no such drug was available before the late 19th century.
she takes a sleeping potion that the Friar made.
In Act IV Scene I
It explains how, later on in the play, the Friar is able to produce a potion which will make a person look dead for 42 hours exactly.
Juliet worries that Friar Lawrence's sleeping potion is actually a poison.
Friar Laurence gives Juliet a potion at the opening of Act 4. It is the only way she can avoid being bigamously married to Paris. It is not a poison, however, just a Mickey Finn designed to knock her out for a couple of days.
she takes a sleeping potion that the Friar made.
Friar Lawrence prepares the potion for Juliet in William Shakespeare's play "Romeo and Juliet."
In Act 5 Scene 3 the Friar describes it as "a sleeping potion."
A potion cooked up by Friar Lawrence.
Friar Laurence
He gives her a potion which will make her appear to be dead.
The Nurse
He gives Juliet a potion will make her seem to be dead on the wedding day.
She will become near-death, her veins will go cold, her heart will stop for 2 days.
He advises her to take a potion which will make her seem to be dead. Then when she wakes up in her tomb, Romeo will come to rescue her.
She threatens to kill herself, so the Friar says that he can give her a knockout potion which will make her seem dead for a couple of days, and then she can come back to life (and get together with Romeo)
The potion that the priest, Friar Laurence gave Juliet to make her appear to be dead would only work for 42 hours which is a little less then two days.