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How Maggot Therapy Works

Learning to Love and Live With Larvae

The FDA considers medical maggots a prescription-only medical device, so you'll need a doctor to prescribe them. You'll also want medical personnel to oversee the process, even as an outpatient. This can be tricky, since not all doctors are comfortable or familiar with MDT.

BioTherapeutics, Education and Research Foundation in Irvine, California, is a nonprofit organization that matches patients with doctors willing to conduct maggot debridement therapy or MDT [source: Gabrielsen].

So how does it work?

To begin, doctors clean the wound, softening it if needed, since maggots much prefer wet and sloppy to hard and dry. They might also protect the nearby skin with a cream barrier if they think irritation likely, since maggot secretions are alkaline and contain ammonia [source: BioMonde].

From there, maggot wranglers have two main options. They can go "free range," sprinkling loose maggots onto the wound before covering it with a breathable dressing. Or they can apply a tea-bag-like polyester pouch that holds the maggots in a sealed sack. The package also contains special foam that helps sustain the critters. Either way, doctors work with farm-raised and sterilized larvae, which they will remove after leaving them in place for about 2-4 days of chowing down and growing. At that time, loose maggots will fall out of the wound, or doctors might pluck them out with forceps or rinse them out with saline [source: NHS]. They bagged variety simply come out with their sachet.

During MDT, patients should avoid bathing or showering, high heat, and anything that will pressure or smother the wound [sources: BioMonde; NHS]. During the first few days, wounds can become sloppy and a bit smelly, but changing the dressing should take care of that [source: Handwerk]. Some wounds will require multiple rounds of maggots, especially those treated with the bagged variety, since sachets prevent the larvae from digging in as deeply as their free-range colleagues do [sources: BioMonde; Jones et al.].

Sources remain mixed on the topic of pain linked to MDT, but it is a risk. Pressure might also build as the maggots grow, but doctors follow strict guidelines covering how many maggots to apply, based on the wound size and the fraction of it that needs debriding.

MDT is not for everyone. Guidelines warn against using it in wounds that bleed easily or that lie near large blood vessels, for example, or on patients taking blood thinners. And, of course, patients should avoid the bagged variety if they have allergies to polyester, PVA, fly larva or the growth medium ingredients, which include soy protein, yeast protein, potato starch and bovine protein [source: NHS].

In fact, MDT does not always beat traditional cures [source: Jones et al.]. But when all else fails, or when high costs place those options out of reach, it nice to know that nature has provided a cheap and effective, if wriggly, alternative.