Maggot Wound Treatment in Dogs (Myiasis)

What Is Myiasis?

Important 2026 update: The New World screwworm has been detected in the southwestern United States (as of June 2026) after being previously eradicated from North America. Screwworm infestations are far more aggressive and require urgent reporting to your veterinarian. VCA Animal Hospitals - myiasis update

Step-by-Step Treatment Protocol

Step 1 - Stabilize and Sedate the Dog

• Assessment and treatment almost always require sedation or general anesthesia - the dog is in pain and larvae burrow deeper when disturbed.
• Common protocol: xylazine (1.1 mg/kg IM) + ketamine (10 mg/kg IM), or equivalent.
• Run bloodwork first in severely affected or systemically ill dogs - check for infection markers and organ function before proceeding.

Step 2 - Clip and Expose the Wound

• Clip all hair around the wound generously - this exposes the full extent of infestation and allows proper cleaning.
• Larvae can migrate to surrounding tissue, so examine the entire surrounding area, not just the visible wound.

Step 3 - Mechanical Removal of Larvae

• Remove all visible larvae using blunt-nosed forceps or by thorough wound flushing.
• Perform aggressive debridement of necrotic tissue - maggots thrive in dead tissue and removing it reduces reinfection risk.
• Place removed larvae in hot water to kill them.

Step 4 - Wound Cleaning and Lavage

• Irrigate thoroughly with chlorhexidine solution (diluted 1:10) and/or povidone-iodine.
• Some protocols also use dilute hydrogen peroxide (3%) for initial cleaning.
• Repeat irrigation until the wound bed is visibly clean.

Step 5 - Antiparasitic Treatment (Kill Remaining Larvae)

Step 6 - Systemic Antibiotics

• Secondary bacterial infection is present in virtually all significant myiasis cases.
• Confirm by wound cytology before starting antibiotics.
• Treat for a minimum of 14 days beyond clinical resolution.
• In severe cases, culture and sensitivity testing guides antibiotic choice.
• Example reported: amoxicillin 500 mg IM (or appropriate weight-based dosing).

Step 7 - Ongoing Wound Management

• Daily dressing changes with wound reassessment for any missed larvae.
• Some wounds require surgical closure once infection is controlled.
• Others heal by secondary intention (open wound management).
• Apply bandages or E-collar to prevent self-trauma and re-infestation.

When to Seek Emergency Care Immediately

• Large number of larvae or deep burrowing
• Dog showing signs of systemic illness (lethargy, fever, not eating)
• Screwworm suspected (especially if dog has traveled to or lives in the southwestern US or Mexico)
• Wound near the eyes, ears, nose, or genitals
• Rapidly worsening wound odor or size

Prevention

• Keep wounds clean and covered; check at least daily.
• Manage underlying skin conditions (allergies, skin folds, matting).
• Keep the coat free of mats, urine, and feces - these attract flies.
• House debilitated dogs indoors or in screened enclosures during fly season.
• Use routine veterinary-approved parasite prevention and repellents.
• Maintain a healthy body weight (obese dogs with skin folds are higher risk).
• Collars should not create skin irritation or pressure wounds.