Harry Potter - Werewolf | Harry Potter Gallery

Harry Potter - Werewolf

A werewolf is a human who, upon the rising of the full moon, turns into a fearsome near-wolf. Werewolves can be distinguished from regular wolves by several small distinguishing characteristics, such as the pupils of the eyes, snout shape, and tufted tail. At all other times, they appear as normal humans, though will often seem to be ill as the full moon approaches.[This condition is caused by infection with lycanthropy, usually occuring when a human is bitten by a transformed werewolf. There is no known cure.

Infection
Lycanthropy is a magical illness known to be spread through oral means; thus, a human bitten by a werewolf in wolf form will become a werewolf him or herself. This is what happened to Remus Lupin, who was bitten as a child by Fenrir Greyback in retaliation for Remus's father offending the werewolf. However, if a human is bitten by a werewolf in human form, the victim will only acquire some lupine tendencies. For example, Bill Weasley retained scars and a craving for very rare meat after being attacked by a non-transformed Greyback.

"My kind don’t usually breed! It will be like me, I am convinced of it – how can I forgive myself, when I knowingly risked passing on my own condition to an innocent child? And if, by some miracle, it is not like me, then it will be better off, a hundred times so, without a father of whom it must always be ashamed!"
—Remus Lupin on his fear that he would pass lycanthropy on to his unborn child.

Werewolves seldom have children, so Remus Lupin did not know whether or not his unborn son would inherit his condition but feared that it would be the case. Teddy Lupin ultimately proved not to be a werewolf, however.

Monthly Transformations
"There was a terrible snarling noise. Lupin's head was lengthening. So was his body. His shoulders were hunching. Hair was sprouting visibly on his face and hands, which were curling into clawed paws."
—Description of Remus Lupin transforming

On every full moon, a werewolf will go through an incredibly painful transformation from a human into a wolf-like creature. They lose the ability to think in a human way, becoming highly aggressive towards humans, even those they are close to. Without any humans nearby to attack, or other animals to occupy it, the werewolf will attack itself out of frustration. This leaves many werewolves such as Remus Lupin with self-inflicted scars and prematurely aged from the difficult transformations.

Treatments
Unfortunately, there is no cure for lycanthropy. However, some of the worst effects can be mitigated by consuming Wolfsbane Potion, which allows a werewolf to retain his or her human mind while transformed, thus freeing them from the worry of harming other humans or themselves. Also, frequent users of this potion seem to refrain from transforming until they are in direct contact with the moonlight.

According to Gilderoy Lockhart, the Homorphus Charm can force a werewolf back into human shape. But, since Lockhart is known to have lied many times to inflate his own reputation and implies that the charm cures werewolves, his information is highly suspect — as is the very existance of a Homorphus Charm in the first place.

Known Werewolves
* Fenrir Greyback — a leader in the werewolf community and an ally of the Death Eaters
* Remus Lupin — bitten by Fenrir Greyback as a child, member of the Order of the Phoenix
* The Wagga Wagga Werewolf — discussed by Gilderoy Lockhart during his time as Defence Against the Dark Arts Professor at Hogwarts; also discussed in his book Wandering with Werewolves. Lockhart may have invented this individual entirely, but since he often simply took credit for other's deeds, the werewolf itself may have existed, but been defeated by someone else.
* A werewolf on Arthur Weasley's ward during his stay at St Mungo's Hospital for Magical Maladies and Injuries, this new werewolf was befriended by Lupin.