Question
It was not left in a cold car.  According to what you say, it DOES get enough light, and it IS sitting in a container with drainage.  

It looked great when I got it; the next day it looked awful.

How could a plant change that drastically overnight?

And, the lady who gave it to me said it was packaged as an "Arrowhead Philodendron".  

It looks like the picture that is on this website: http://www.aecnetwork.com/gardening/plants_info/arrowhead_philodendron.htm

Is there anything else I can do?  You haven't really given me anything new, other than what I already said.

Can a withered plant be revived?

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The text above is a follow-up to ...

-----Question-----
Hello.  I was given an Arrowhead Philodendron about four days ago.  I brought it back to my apartment, and it's been sitting next to the window, but it's definitely indirect light, even low light, because I only have one window.  I watered it once, because it was pretty dry when I got it.

About half of the plant is now wilted and it looks awful; it's only been four days, and it's looked like this since day 2.  I've been reading up on Philodendrons and I can't figure out where I've gone wrong, because everything says they require indirect lighting, but can stand low indoor lighting, and they should be watered when their soil is dry.  My dad used to have one, and he never even kept it near a window...

The only thing I can figure is a change in location/environment.  Also, I have NO idea if this is any bearing, but the person I got it from was a big indoors smoker.  I don't smoke.  

What can I do to revive or help perk up my plant?
-----Answer-----
Lauren,

It needs enough light that your hand would make a good shadow without turning on a light or for you to read a paperback novel sitting where it sits without turning on a light. If the leaves are arrow shaped it is a nepthitus, not a philodendron. The care is about the same though. Is it in a pot with a hole in the bottom for drainage? If not it is sitting in a swamp and that is the problem. Otherwise was it left in a cold car before it was given to you? Problems that appear in 4 days usually started long before that. The symptoms indicate either too little water or too much or not enough light. Good luck in figuring it out.

Darlene

Answer
Lauren,

I know the plant on your website as Butterfly Nephthytis or it's latin name Syngonium podophyllum. I have no idea what but it has to have been caused by something that happened to it before you received it. Smoke would not have caused the problem. The wilted leaves will not revive. Cut those off at the base of the stem with sharp scissors.

Be very careful not to overwater it. Set it in the sunniest location available, that may help it regrow faster. Do not fertilize it now, wait until it seems to have stabilized then monthly doses of half strength water soluable fertilizer such as Miracle Grow would help. As long as it is no longer wilting it should regrow.  That plant was the first houseplant I ever had when I was 8 years old and got my tonsils out. It is a resilient plant and should come back. It will just take time. I have no idea what caused it but it happened before you received it. Freezing temps even going from the car to the house without it being in a bag could have caused it. That's just a guess. Good luck.

Darlene