This is aboutn Lupin's potion I think there's a missunderstandnig coz they say that he should take the potion in the week before full moon. But Snape gave him the potion the night of the full moon.

"The potion Profeeser Snape has been making for me is very recent discovery.It makes me safe,you see.As long as i take it in the week Proceeding the full moon."p.352,353.

But when Lupin starts transfering Hermione said:-
"Oh my- He didnt take his potion tonight! He's not safe"

While that night was the night of hte full moon.

Curuios isnt it.
If anyone know any good explanation for this post it here

its probably something like if he doesnt take it the whole week leading up to it including the day of, he turns into a really bad Were. Becuase isnt the potion make him keep his own mind while he's a wolf? So probably if he doesnt take the potion, he wont have complete control over himself.

This is from Wikipedia - Potions in Harry Potter
Potions in Harry Potter - Wikipedia, the free encyclopedia

Wolfsbane Potion is a recently (around 1990) invented potion that, if taken periodically during the week leading up to the full moon, allows a werewolf to retain his or her mindset and sanity, when he/she transforms into a werewolf during the full moon.

It is described as a foul-tasting potion - sugar makes it useless - and is so difficult to make that Severus Snape is the only member of the Hogwarts staff capable of preparing the potion for Remus Lupin, who requires regular doses to control himself when he transforms into a werewolf.

The potion was invented by Marcus Belby's Uncle Damocles. Damocles was taught Potions in Hogwarts by Horace Slughorn. It is not known whether the Wolfsbane Potion is made from any part of the plant called wolfsbane.

If the potion does not stop the transformation, how does Hermoine know he's not safe? Why would Lupin not have taken the potion? I wonder if the potion is taken regularly, does it's effect lessen?

I guess because hermoine reads a lot. JKR said that if she needs to tell the readers something, she lets Hermione (or Dumbledore) say it.

The potion is so that the transformation isn't as painful for Lupin to go through. I'm not sure how often it needs to be taken though.

Periodic means Happening or appearing at regular intervals; intermitent. So that would suggest Lupin needed to drink it at least every other day. I guess every day would be better though. I wonder if you can drink too much of that potion if it would have any odd effects?

See, he says if he takes it IN THE WEEK, so if he takes it the night before he would stil be safe, cause thats IN the week, innit?

I agree with that! The night of the full moon is still in the week before.

I've always wondered about why he only transforms once a month though. There are three days where the moon is full so why does he only transform once?

He must have to take it every night in the week before and the night of the full moon to make it work.

Interesting question though!

It must be annoying for him to have to take it though. i mean he says it tastes like tea but without the sugar or something like that in one of the books so surely there must be some way Severus could make it taste better? I mean he is one of the best Potions Masters there is!

Cool i didnt katch that one I bet snape needed an excuse to enter lupen's office

Remus was maybe too preoccupied that's why he had forgotten to drink the potion but to your question i think, Hermione meant that he hadn't drank the potion for that full moon. The potion will have an effect if it was drank before the full moon.