Welcome to Brainstuff from dot com where smart happens. There's a new show on Discovery Channel called Monsters Inside Me, and it fits perfectly with today's question. What is a medical leech? You may have never seen a leech before. They come in a variety of shapes and sizes, but medical leeches look a lot like a long slug about the size of your finger. They have a mouth at the second end that attaches quite firmly, and the leech
will about double in size as it feeds. This sounds rather unpleasant, but leeches turn out to be useful in medicine. If you've ever had microsurgery on an extremity like a finger or an ear lobe, one post surgery problem you get involves blood flow. By attaching a leech, a patient gets several benefits. For one, the leech pulls blood through the extremity as it feeds. For another, it injects a
helpful anticoagulant that improves blood flow. And because of the whole and that anticoagulant the leech leaves behind, there will be bleeding after the leech falls off, and it's also helpful to healing. Medical leeches are raised in captivity, so they're sterile to a certain degree. If you want to buy one, you can go find them on the internet for about seven bucks each. Leeches are not the only
medically useful parasite. You can also buy medical maggots. These little worm like creatures are put into bad wounds to clean them out. The maggots will eat dead flesh, but leave living flesh alone. After a day or two, the wound is cleared of all the dead flesh and healing usually proceeds much more quickly. If you enjoy parasites like leeches, be sure to check out Monsters Inside Me on the Discovery Channel Wednesdays at nine pm. Do you have any
ideas or suggestions for this podcast? If so, please send me an email at podcast at how stuff works dot com. For more on this and thousands of other topics, go to how stuff works dot com and be sure to check out the brain stuff blog on the how stuffworks dot com home page.