Gone are the days of castor oil for constipation and butter for soothing burns -- many of these old-time home remedies really don't work like you thought they did, and some may even be harmful.

Can castor oil really ease constipation? Does butter really make burns better? While grandma may insist these old-time home remedies work, most of them don't, and in fact, some may even be harmful.

Experts take a look at remedies of old, suggest why some might be better off retired, and provide direction for what to use instead.

1. Castor Oil

The thinking: It's a laxative that's naturally derived from the castor bean plant, and if taken regularly, the thinking is it can make you -- you guessed it -- regular. But just because it comes from a plant doesn't mean you should overdo it.

What it actually does: Castor oil is a stimulant laxative, according to the Mayo Clinic, which causes the muscles of the intestines to contract, and push stool forward. It's fast-acting, with results in two to six hours, and is among the most powerful laxatives out there. But these types of laxatives can cause side effects, including cramping, diarrhea, or nausea. And if taken regularly, like most laxatives, castor oil can actually aggravate constipation. Your body can become dependent on it for all bowel movements. Worst case, overuse can damage the nerves, muscles, and tissues of the large intestine.

What to do instead: Use castor oil and other stimulant laxatives only as a last resort, and after talking to your doctor, the Mayo Clinic says. Remember that you can become dependent on laxatives, so avoid overuse.

2. Butter

The thinking: Butter can act like a salve and help a burn heal.

What it actually does: Butter doesn't always make everything better: According to the Red Cross, putting butter on a burn can trap heat in, increasing the risk of infection.

What to do instead: The proper care and treatment of a burn is to cool a burn -- and don't misinterpret that to mean put ice on it, which can further damage tissue, says Victoria VanderKam, RN, program director of the University of California at Irvine Regional Burn Center.

For less severe burns in which only the outer layer of the skin is burned, VanderKam recommends, Cool the burn for 10-15 minutes by immersing it in cool water, and then put some antibiotic ointment on it and cover it with a Band-Aid.

For severe burns that are deep or cause severe blistering, or for burns that cover more than 10% of the body, seek medical attention immediately, VanderKam tells WebMD.

3. Hydrogen Peroxide

The thinking: Many people use hydrogen peroxide as an antiseptic, thinking the bubbles are a clear sign that it's killing germs.

What it actually does: Hydrogen peroxide is better used as an agent to clean a wound of debris, but not as an agent to kill bacteria, says Thomas A. Kintanar, MD, a board member of the American Academy of Family Practice.

What to do instead: After you've cleaned a wound with hydrogen peroxide, use rubbing alcohol as an antiseptic, which provides a broad spectrum of coverage -- killing microbes, fungi, viruses, etc., says Kintanar, who has a private practice in Fort Wayne, Ind. And then for the coup de grace, place some triple antibiotic ointment on it and cover it with a Band-Aid.

4. Syrup of Ipecac

The thinking: Syrup of ipecac is most commonly known as a routine home remedy for poison ingestion.

What it actually does: Plant-derived, ipecac is a stomach irritant that induces vomiting. The American Academy of Pediatrics (AAP) now recommends that syrup of ipecac no longer be used routinely as a home treatment strategy.

Why the change in reputation of one of the most recognized home remedies?

An AAP policy statement says, Although it seems to make sense to induce vomiting after the ingestion of a potentially poisonous substance, it was never proven to be effective in preventing poisoning. Recent research has failed to show benefit for children who were treated with ipecac.

The American Association of Poison Control Centers (AAPCC) in Washington takes a slightly different tack.

The American Association of Poison Control Centers believes that ipecac may well be indicated in rare circumstances, says Rose Ann Soloway, associate director of the organization.

What to do instead: The controversy over ipecac aside, Soloway, the AAPCC and the AAP recommend that no matter the situation, if poison is ingested, always call the Poison Center first.

Pick up the telephone and call the poison center, Soloway tells WebMD. You never have to worry about what the right thing to do is -- it's a 24-hour, seven-days-a-week emergency number, and when you call the poison center, you will get immediate expert advice that is tailored to the needs of the person who has been exposed. The number is 800-222-1222.

5. Skin-So-Soft

The thinking: It smells pretty, it makes your skin feel, well, so soft, and the thinking is it helps keep bugs at bay.

What it actually does: Researchers at the University of Chapel Hill in North Carolina looked at 16 different products, including Skin-So-Soft, for their mosquito-repellent qualities, according to a news release. After applying one of the products to the arms of a volunteer, researchers asked the person to stick his arms in a mosquito cage.

According to the release, after testing various Skin-So-Soft products, including those containing the chemical IR3535 or plant-based citronella, protection lasted, on average, far less than 20 minutes. More recently marketed products that contain oil of eucalyptus as the repellent -- such as Fite Bite and Repel -- lasted an average of two hours .

What to use instead: Products with DEET showed by far the greatest effectiveness in preventing mosquito bites, the release stated. OFF! Deep Woods, which consists of 23.8% DEET, lasted on average five hours, while OFF! Skintastic, with 6.65% DEET, lasted about two.

6. Whiskey

The thinking: In addition to its inebriating effects, some people believe whiskey can help relieve tooth or gum pain.

I suspect people think whiskey is something of an analgesic, says David A. Russell, DMD, associate dean at Tufts University School of Dental Medicine.

While adults could use their tooth pain as an opportunity to imbibe, people have also been known to use it on teething babies.

When babies' teeth were coming through, I remember people recommending putting whiskey on your finger and then rubbing it on a baby's gums, says Russell.

What it actually does: If the pain is in the tooth, and it's a nerve that is inflamed, there is no way whiskey will do anything, says Russell. And, if it's gum pain, maybe there's some soothing effect of the actual alcohol against the gum tissue, but that's it. At the very best, this whiskey business just made people feel better if they used enough of it.

What to do instead: Pain, especially in the tooth or gums, is a sign of some harmful process going on, says Russell. The most immediate thing you should do is call your dentist.

Russell explains aspirin is another home remedy for tooth pain that doesn't work.

Another myth is to put an aspirin tablet on the tooth or gum, says Russell. This is dangerous because aspirin is very acidic -- you can actually see the round imprint of the tablet burned into the gum where the person put the aspirin tablet.

Aspirin should never be given to children or infants because it is associated with Reye's syndrome. To soothe teething pain, parents can give infant-formula ibuprofen or acetaminophen, rub their gums, and provide safe items for them to chew.

Published March 24, 2004 by Heather Hatfield; Reviewed By Brunilda Nazario, MD