Why Did Mrs. Crouch Die While Taking Polyjuice Potion?

Question

So I've been re-reading Goblet of Fire and after reading Barty Crouch Jr's recounting of how he and his mother switched places in Azkaban via Polyjuice Potion, I'm unclear why Mrs. Crouch died while she was still taking Polyjuice.

If Mrs. Crouch's body was terminally ill, each time she took the Polyjuice wouldn't she have had Barty Crouch Jr's body, which was not terminally ill? Why, then, did she die very soon after Barty Crouch Jr was smuggled out of Azkaban? Shouldn't she have had her son's strength and health from the Polyjuice? Yes, Barty Crouch Jr was weakened by Azkaban, but he wasn't dying.

Deathly Hallows shows that the physical limitations or disabilities of the person providing the hairs for the Polyjuice Potion are transferred to the person taking the potion:

‘Harry, your eyesight really is awful,’ said Hermione, as she put on glasses.

_{Deathly Hallows -- page 49 -- Bloomsbury -- chapter 4, The Seven Potters}

It would seem the same would go for healthy characteristics. As long as Mrs Crouch had a supply of Polyjuice Potion, shouldn't she have remained alive? It could be said that she ran out of Polyjuice and then died, but Barty Crouch Jr says implicitly that his mother died with Barty Jr's appearance, meaning the Polyjuice was still in her system and working at the time of her death.

Why did Mrs. Crouch die while taking Polyjuice Potion?

Answer 1

I believe it has everything to do with the limitations of the Polyjuice potion. Since we don't know what she died of, disease seems the most likely to me. And by looking at the effects of polyjuice potion, if my theory is right, it would explain why it didn't keep her alive.

Polyjuice potion alters the appearance of a person, meaning altering physical external characteristics to match that of the person being copied. It's clear that the polyjuice potion does not alter everything about the drinker. Some things must remain unchanged. For example, it must leave the brain alone, or the user would lose his or her personality.

Poor eyesight generally has to do with the shape of the cornea, or damage to it - an outward physical trait that would be copied exactly the same as the shape of the lips or leg. Hermione's eyesight was affected simply due to outward physical changes. It had nothing to do with sickness or disease.

Polyjuice potion appears to affect the shape of the body - at many levels, and various body parts, and also the color of the skin, hair, etc to effect the transformation. Diseased flesh, transformed to a different shape and/or color is still diseased.

Answer 2

We are never told what terminal illness that she has, but your assessment that physical characteristics seem to be transferred with the Polyjuice Potion is spot on. What we know that isn't transferred with the Polyjuice potion is the person's mind.

Therefore it seems most likely that the terminal illness with which Mrs. Crouch was dealing with, was a mental illness. In canon we see numerous techniques that wizards can use to heal physical maladies, yet the only (IIRC) mental malady that we know of; Neville Longbottom's parents, is apparently not treatable. Indeed there are several patients in the mental wing of the hospital. Perhaps in the wizarding world the treatment of mental illnesses is not something that magic provides much help with.

There is also this quote from the relevant passage in The Goblet of Fire:

They sensed one healthy, one dying person entering Azkaban. They sensed one healthy, one dying person leaving it.

So Barty Crouch Jr. was already dying inside Azkaban, so even if the Polyjuice potion gave her his health, he was already dying at that point (so much so that the Dementors did not notice his health compared to his mothers).

Answer 3

She possibly died from the same disease as someone from a totally different canon - Padme Amidala. From a broken heart, aka. loss of will to live.

She was already on the way there at Barty Jr.'s trial as seen in Dumbledore's Pensieve memories:

There was total silence, broken only by the dry sobs of a frail, wispy-looking witch in the seat next to Mr. Crouch. She was clutching a handkerchief to her mouth with trembling hands.

...

The wispy witch beside him gave a great gasp and slumped in her seat. She had fainted. Crouch appeared not to have noticed.

Answer 4

Here's my take. The intention behind polyjuice is to give the appearance you are someone else.

However, copying a fatal disease would be a bad idea. Losing your brain/memories would also be bad. Given polyjuice has been created by someone, and is well known/well used, it must have been well thought out and tested.

I think polyjuice would change what is necessary for the change to be authentic, without endangering you/your sanity.

If your face needs to change, it will. If your voicebox needs to change, it will. If you need to stumble around blindly without glasses, you will (nice one David Stratton, great example).

If the person you're copying is ill or mad, it's far safer to just act like you have that particular fatal disease, or that you're mentally ill. This would result in a very useful potion, instead of a possibly deadly potion.

With this in mind, I definitely took the 'one healthy/one dying' to mean his mum was dying, and he wasn't, and the polyjuice was for people who could see him. It makes more sense. If everyone thinks he's died inside, great. If his mum is terminal, why not pull this off? She's dying anyway.

The alternative is far less believable; his non-terminal mum swaps with him then dies. He's terminal then escapes and recovers.

As for his need to recover, I don't think it's related to dying. Azkaban is regarded as a pretty terrible place. It's entirely believable you'd need to recover after leaving. I think I would.

Answer 5

I think the questioner, in this case, is thinking a little too much about the minute, undiscussed details of magic. I actually doubt that even J.K. Rowling thought of this herself. The problem with questions like this is that they tend to be answered with superfluous real-world knowledge of science or some other field. Everything Slytherincess says about the transfer of health-status accompanying the shape-shifting powers of Polyjuice Potion is very well thought out, with a lot of real-world logic applied to it - but that is just the problem, unfortunately: it's real-world logic applied to the illogic of magic. All we know about the Polyjuice Potion is that it is designed to make one human look (and sound) exactly like another; how and why the disease of Mrs Crouch wouldn't have been cured by Barty Crouch Jr's essence in the Polyjuice Potion is unanswerable. I'm afraid we don't know. To provide any other sort of explanation is just speculation. However, since Mrs Crouch did still have her disease whilst in her son's form, we have proof that drinking Polyjuice Potion with the hairs of a healthy person in it will not cure someone of a disease; within J.K. Rowling's world, anyway.

Answer 6

Polyjuice is a disguise and just that; it would not reporduce/cure illness, simply give the outward appearance of them as much as required; she still died, despite being in Barty's form. Along with the mind, there are obvious limitations to the change.

Barty appeared to be dying to the Dementors, because that was part of the apperance the Polyjuice was required to create. The 'nursing back to health' would be from Azkaban's after affects; if he was truly dying, then he wouldn't have been able to recover, and would have made his mother's trade pointless.

Alternativly, they both could have had illness (retained in the change) and the Dementors couldn't tell the difference/couldn't be bothered; Mrs. Crouch's decline since the trial, and Barty's Dementor-fed-upon mind. His was environmental, so once clear of it, he could recover, but she would get worse, and succumb.

The dementors didn't check the disguised Mrs. Crouch. They made sure the same 'feeling' people came and left; anyone sneaking in would be illogical to them. They could have sensed her misery, but they wouldn't have considered that amiss in Azkaban.