A couple of postings have already stated this - unfortunately, the itch won't be totally gone until your body has reabsorbed the "feeding tube" it created when the chigger bit your skin.
If you've been outdoors, be sure to shower soon afterwards to remove any leftover critters, and wash your clothes too, as soon as practical.
If you've been biten, popular anti-itch lotions, topical analgestics and/or antiseptics, and in extreme cases the use of prescription medications, PLUS time, are the only relief available. You can use nail polish - but its not a cure - mostly a reminder not to scratch the welt. As already mentioned on this site, though chiggers do not carry disease, scratching the affected area may lead to a secondary infection - something you want to avoid - so, wash up well, apply OTC products to alleviate the itch, and see a physician if the bites are extremely bad, or are really bothering you.
Having grown up in central Missouri, playing outdoors in the woods and tall grasses was a daily event. Before going out, mom would douse our clothing (leg, waist and arm openings) with powdered sulfur (also known as "flowers of sulfur"). You don't need to eat matches, folks, but sulfur works - ask any hunter. BUT be forewarned - sulfur stinks. Powdered sulfur is available at pharmacy stores.
The Missouri Department of Conservation has a good article on chiggers, their bites, prevention, relief, etc. - recommended reading for those unfamiliar with the chigger mite. http://mdc.mo.gov/nathis/arthopo/chiggers/
The best remedy for chigger bites is prevention. If you are going to be in a chigger infested area, wear appropriate clothes (not sleeveless shirts, shorts or sandles), and dust the openings (leg and waist) of your clothes with powdered sulfur (also known as "flowers of sulfur") which can be purchased at pharmacies. Yes, it stinks, but this is about the only prevention product out there that is tried & true. Here is a link to a Missouri Department of Conservation article that backs up this advice. http://mdc.mo.gov/nathis/arthopo/chiggers/.
This article acknowledges several of the remedies posted here but in fact, the only true remedy is time. When the chigger bites, the body reacts by hardening the cells around the bite area. These hardened cells become the chigger's feeding tube. Though the chigger will be long gone, the itch will remain until your body has reabsorbed these cells.
I suggest that you read the article, its a solid page long and very imformative. Having grown up in central Missouri and spending a lot of time in the woods and tall grasses, sulfur is, by far, the best prevention product. And once bitten, thorough washing and standard itch remedies, plus time, will heal all wounds. Enjoy the outdoors and good luck.
