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Screw Worm Aerosol

This page contains information on Screw Worm Aerosol for veterinary use.
The information provided typically includes the following:
  • Screw Worm Aerosol Indications
  • Warnings and cautions for Screw Worm Aerosol
  • Direction and dosage information for Screw Worm Aerosol

Screw Worm Aerosol

This treatment applies to the following species:
Manufacturer: Aspen

Wound Spray:

Kills flies and fly maggots on wounds.

For Use On:

Beef and Dairy Cattle, Sheep, Goats, Swine and Horses.

EPA Reg. No. 47000-100-40940

EPA Est. No. 47000-IA-1


Screw Worm Aerosol Caution

Active Ingredients







*(3-phenoxyphenyl) methyl (+/-) cis/trans 3-(2,2-dichloroethenyl)-2,2-diemethylcyclopropanecarboxylate (Cis/Trans ratio: Min. 35% (+/-) cis and max 65% (+/-) trans.)

** Contains Petroleum Distillates

Precautionary Statements


Screw Worm Aerosol Caution

Harmful if swallowed, absorbed through the skin or inhaled. Causes moderate eye irritation. Avoid breathing spray mist. Avoid contact with skin, eyes or clothing. Wash thoroughly with soap and water after handling and before smoking or eating. Remove contaminated clothing and wash before reuse. Avoid contamination of feed and foodstuffs.

Environmental Hazards

This product is extremely toxic to aquatic organisms, including fish and invertebrates. To protect the environment, do not allow pesticide to enter or run off into storm drains, drainage ditches, gutters or surface waters. Applying this product in calm weather when rain is not predicted for the next 24 hours will help ensure that wind or rain does not blow wash pesticide off the treatment area. Rinsing application equipment over the treated area will help avoid run off to water bodies or drainage systems.

This product is highly toxic to bees exposed to direct treatment on blooming crops or weeds. Do not apply this product or allow it to drift to blooming crops or weeds while bees are actively visiting the treatment area.


Contents under pressure. Do not use or store near heat or open flame. Do not puncture or incinerate container. Exposure to temperatures above 130°F may cause bursting.

First Aid

Have Product Container or Label with You When Calling a Poison Control Center, Doctor or Going in for Treatment.

If Inhaled:

● Move person to fresh air.

● If person is not breathing, call 911 or an ambulance, then give artificial respiration, preferably mouth to mouth, if possible.

● Call a poison control center, doctor, or 1-800-498-5743 for treatment advice or transport the patient to the nearest hospital.

If Swallowed:

● Call a poison control center, doctor, or 1-800-498-5743 immediately for treatment advice or transport the patient to the nearest hospital.

● Do not give any liquid to the patient.

● Do not administer anything by mouth to an unconscious person.

● Do not induce vomiting unless told to do so by the poison control center or doctor.

If in Eyes:

● Hold eye open and rinse slowly and gently with water for 15-20 minutes.

● Remove contact lenses, if present, after first five minutes, then continue rinsing eye.

● Call a poison control center, doctor, or 1-800-498-5743 for treatment advice or transport the patient to the nearest hospital.

If on Skin or Clothing:

● Take off contaminated clothing.

● Rinse skin immediately with plenty of water for 15-20 minutes.

● Call a poison control center, doctor, or 1-800-498-5743 for treatment advice or transport the patient to the nearest hospital.

NOTE TO PHYSICIAN: Contains petroleum distillate. Vomiting may cause aspiration pneumonia.

For 24-hour emergency information on this product, call 1-800-498-5743 (US & Canada) or 1-651-523-0318

Directions For Use

It is a violation of Federal law to use this product in a manner inconsistent with its labeling.


Read the entire label and follow all use directions, use restrictions and precautions.


● Do not breathe dust, vapors or spray mist.

● Do not apply when food is present.

● When used in dairy barns and facilities: Close milk bulk tank lids to prevent contamination from spray and from dead or fallen insects. Remove or cover milking utensils before application. Wash teats of animals before milking.

● When applying as a space spray, remove people and pets from the area before spraying. Except when apply to pets or livestock, do not enter or allow others to enter until spray shave dried.


Remove protective cap, hold container upright and spray from a distance of 12 to 15 inches.

IN ANIMAL QUARTERS AND MILK ROOMS: For rapid control of House Flies, Mosquitoes, Gnats, Wasps, Bees, and Small Flying Moths. Remove animals prior to treatment, close windows and doors and spray at the rate of 2 seconds per 1000 cubic feet of space. For best results, keep area closed for 10 minutes after spraying. Do not remain treated area and ventilate after treatment is completed.

TO TREAT LIVESTOCK: To protect beef cattle, dairy cattle, goats, sheep, hogs and horses from attacks of Stable Flies, Horse Flies, Deer Flies, Face Flies, House Flies, Horn Flies, Mosquitoes, Ticks and Gnats: Spray about 3 seconds on each side being careful to spray back, withers and forelegs thoroughly. To protect from Face Flies, spray the face and head, but do not spray into eyes. Repeat treatment when flies are troublesome. For ear ticks spray directly into ear.

WOUND SPRAY AND TO KILL SCREW WORMS, FLIES, AND MAGGOTS INFESTING BEEF CATTLE, HORSES AND SHEEP: Hold can about 4 to 8 inches from the area to be treated with muzzle pointed at wound. Spray the area until it is completely wet (3 to 10 seconds are usually enough). The area surrounding the wound should also be sprayed. This product is not recommended for use in deep wounds.

Note on Resistance: Some strains of screw worm may develop resistance to pyrethroids. This will be observed by lack of response to treatment. Where pyrethroid resistance is known or suspected, this product should not be used.

FOR SWINE: Do not ship animals for slaughter within 5 days of last treatment.

TO CONTROL BLOOD SUCKING LICE: Apply to the infested areas of the animals, using a stiff brush to get the spray to the base of the hair. Repeat every three weeks if required.

TO CONTROL POULTRY LICE: Spray roosts, walls and nests or the cages thoroughly. This should be followed by spraying over the birds with a fine mist.

FOR CONTROL OF BEDBUGS AND MITES IN POULTRY HOUSES: Spray crevices of roost poles, cracks in walls and cracks in nests where the bedbugs and mites hide.

Storage And Disposal

Do not contaminate water, food, or feed by storage or disposal.

PESTICIDE STORAGE: Store in a cool, dry secure area in original container.

PESTICIDE DISPOSAL: Wastes resulting from the use of this product may be disposed of on site or at an approved waste disposal facility.

CONTAINER HANDLING: Non-refillable container. Do not reuse this container. If empty: Place in trash or offer for recycling if available. If partly filled: Call your local solid waste agency for disposal instructions. Never place unused product down any indoor or outdoor drain.


To the extent permitted by applicable law, seller makes no representation or warranty, either expressed or implied, for results due to misuse, improper handling or improper storage of this material. Nor does Seller assume any responsibility for injury to persons, crops, animals, soil or property arising out of misuse, improper handling or improper storage of this material.

Manufactured For: Aspen Veterinary Resources,® Ltd., Liberty, MO 64068



12 oz (354.88 mL)

A246N Rev. 04/17

CPN: 1475278.1

Telephone:   816-415-4324
Fax:   816-415-4314
Every effort has been made to ensure the accuracy of the Screw Worm Aerosol information published above. However, it remains the responsibility of the readers to familiarize themselves with the product information contained on the US product label or package insert.

Copyright © 2019 Animalytix LLC. Updated: 2018-11-30