Maggot therapy. Wound of a patient suffering from a leg ulcer 3 days after treatment with maggot therapy. The wound is a healthy pink colour and healing. Larvae (maggots) of the greenbottle fly (Lucilia sericata) are used to clean wounds by eating dead and dying flesh and leaving healthy tissue. They clean the wound more efficiently than drugs or other treatments and prevent the onset of gangrene and septicaemia. The maggots prevent the growth of harmful bacteria in the wound by altering the acidity and releasing an antibiotic compound. Only this species of maggot, which are bred in sterile conditions, are used for medical purposes.