Malathion is the poisonous ingredient in these products.

Malathion is used in agriculture to kill and control insects on crops and in gardens. Government agencies also use it to kill mosquitoes in large outdoor areas.

Malathion may also be found in certain products used to kill head lice.

Below are symptoms of malathion poisoning in different parts of the body.

AIRWAYS AND LUNGS

• Chest tightness
• Difficulty breathing
• Wheezing
• Increased airway secretions or mucus
• No breathing

BLADDER AND KIDNEYS

• Increased urination
• Inability to control urine flow (incontinence)

EYES, EARS, NOSE, AND THROAT

• Increased salivation
• Increased tears in the eyes
• Small pupils
• In some cases, pupils may be dilated and do not react to light

HEART AND BLOOD

• Low or high blood pressure
• Slow heart rate
• In some cases, heart rate may be rapid
• Weakness

NERVOUS SYSTEM

• Agitation
• Anxiety
• Coma
• Confusion
• Convulsions
• Dizziness
• Headache
• Muscle twitching

SKIN

• Blue lips and fingernails
• Sweating

STOMACH AND GASTROINTESTINAL TRACT

• Abdominal cramps
• Diarrhea
• Loss of appetite
• Nausea and vomiting

Call the poison control center for treatment information. If malathion is on the skin, wash the area thoroughly for at least 15 minutes.

Throw away all contaminated clothing. Follow instructions from the appropriate agencies for getting rid of hazardous waste. Wear protective gloves when touching contaminated clothing.

Have this information ready:

• Person's age, weight, and condition
• Name of the product (ingredients and strength, if known)
• Time it was swallowed
• Amount swallowed

The local poison control center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere in the United States. This national hotline will let you talk to experts in poisoning. They will give you further instructions.

This is a free and confidential service. All local poison control centers in the United States use this national number. You should call if you have any questions about poisoning or poison prevention. It does NOT need to be an emergency. You can call for any reason, 24 hours a day, 7 days a week.

You can also get online poison help now at Poisonhelp.org. Just enter the product, poison, or medicine to get expert help.

Take the container with you to the hospital, if possible.

People with malathion poisoning will likely be treated by first responders (firefighters, paramedics) who arrive when you call the local emergency number. These responders will decontaminate the person by removing the person's clothes and washing them down with water. The responders will wear protective gear. If the person is not decontaminated before getting to the hospital, emergency room personnel will decontaminate the person and provide other treatment.

Your health care provider at the hospital will measure and monitor your vital signs, including temperature, pulse, breathing rate, and blood pressure. You may receive:

• Blood and urine tests
• Breathing support, including oxygen, or a tube that goes through the mouth into the lungs, and attachment to a breathing machine (ventilator)
• Chest x-ray
• Head CT (computerized tomography) scan
• Electrocardiogram (ECG)
• Intravenous fluids (fluids given through a vein)
• Medicine to reverse the effects of the poison, which may include atropine or pralidoxime
• Tube placed down the nose and into the stomach (sometimes)
• Washing of the skin (irrigation) and eyes, perhaps every few hours for several days

People who continue to improve in the first 4 to 6 hours after receiving medical treatment usually recover. Prolonged treatment often is needed to reverse the poisoning. This may include staying in the hospital intensive care unit and getting long-term therapy. Some effects of the poison may last for weeks or months, or even longer.

Keep all chemicals, cleaners, and industrial products in their original containers and marked as poison, and out of the reach of children. This will reduce the risk of poisoning and overdose.

Carbofos poisoning; Compound 4049 poisoning; Cythion poisoning; Fosfothion poisoning; Mercaptothion poisoning

Agency for Toxic Substances and Disease Registry (ATSDR) website. Toxic substances portal: toxicological profile for malathion. wwwn.cdc.gov/TSP/ToxProfiles/ToxProfiles.aspx?id=522&tid=92. Reviewed March 20, 2014. Accessed April 15, 2025.

Aminoff MJ, So YT. Effects of toxins and physical agents on the nervous system. In: Jankovic J, Mazziotta JC, Pomeroy SL, Newman NJ, eds. Bradley and Daroff's Neurology in Clinical Practice. 8th ed. Philadelphia, PA: Elsevier; 2022:chap 86.

Welker KL, Thompson TM. Pesticides. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 152.

Updated by: Jesse Borke, MD, CPE, FAAEM, FACEP, Attending Physician at Kaiser Permanente, Orange County, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.