Bug spray poisoning
This article discusses the harmful effects from breathing in or swallowing bug spray.
This is for information only and not for use in the treatment or management of an actual poison exposure. If you have an exposure, you should call your local emergency number (such as 911) or the National Poison Control Center at 1-800-222-1222.
Most bug repellents contain DEET (N,N-diethyl-m-toluamide) as their active ingredient. DEET is one of the few insect repellents that work. It is recommended to prevent mosquito-born diseases such as malaria, dengue fever, and West Nile virus.
Other less effective forms of bug sprays contain pyrethrins. Pyrethrins are a pesticide created from the chrysanthemum flower. It is generally considered nontoxic, but it can cause breathing problems if you breathe in large amounts.
Bug sprays (insect repellents) are sold under various brand names.
- Breathing difficulty
- Loss of alertness due to imbalance in oxygen level
- Tremors (if a large amount is swallowed)
- Seizures (if a large amount is swallowed)
- Upset stomach
Persons applying DEET to their skin may get hives or have mild redness and irritation. These symptoms are usually mild and will go away when the product is removed from the skin.
Persons who use very high concentrations of DEET on their skin over a long period of time (such as military personnel or game wardens) may have more severe skin reactions that include blistering, burning, and permanent scars of the skin. Other symptoms associated with long-term use of high amounts of DEET (over 50% concentration) include insomnia and mood changes.
If DEET is unintentionally sprayed into the eyes, nose, or mouth, you may feel a temporary burning sensation and have redness. Washing the area will usually make the symptoms go away. Burns to the eye may require medication.
When small amounts of DEET are swallowed by mouth, symptoms may include:
- Moderate to severe stomach irritation
Low blood pressure (hypotension) and low heart rates (bradycardia) may occur if a large amount is swallowed.
By far, the most serious and devastating complication of large DEET poisonings is neurological damage. Patients may have disorientation, clumsiness when walking, seizures, or coma. Death is possible in these cases.
DEET is especially dangerous for small children. Seizures may occur in small children who are consistently exposed to DEET on their skin for long periods of time. Care should be taken to only apply lower concentrations of DEET to children for short periods of time. Products containing DEET probably should not be used on infants.
Do NOT make a person throw up unless told to do so by poison control or a health care professional. Seek immediate medical help.
If the chemical is on the skin or in the eyes, flush with lots of water for at least 15 minutes.
If the chemical was swallowed, immediately give the person water or milk, unless instructed otherwise by a health care provider. Do NOT give water or milk if the patient is having symptoms (such as vomiting, convulsions, or a decreased level of alertness) that make it hard to swallow.
If the person breathed in the poison, immediately move him or her to fresh air.
Before Calling Emergency
Determine the following information:
- The patient's age, weight, and condition
- The name of the product (ingredients and strengths, if known)
- The time it was swallowed or inhaled
- The amount swallowed or inhaled
The National Poison Control Center (1-800-222-1222) can be called from anywhere in the United States. This national hotline number 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.
Take the container with you to the hospital, if possible.
See: Poison control center - emergency number
What to Expect at the Emergency Room
The health care provider will measure and monitor your vital signs, including temperature, pulse, breathing rate, and blood pressure. Symptoms will be treated as appropriate. You may receive:
- Activated charcoal
- Breathing support, including a tube through the mouth and into the lungs, connected to a breathing machine (ventilator)
- Bronchoscopy -- camera down the throat to see burns in the airways and lungs
- Chest x-ray
- EKG (heart tracing)
- Fluids through a vein (IV)
- Medication to treat the effects of the poison
- Tube through the mouth into the stomach to wash out the stomach (gastric lavage
- Washing of the skin (irrigation) -- perhaps every few hours for several days
Severe asphyxiation can be rapidly life-threatening. For simple exposure or inhalation of small amounts, recovery should occur.
When used as directed in low doses, DEET is relatively not harmful. It is the preferred bug repellent for the prevention of mosquito-borne illnesses such as Dengue fever, malaria, and West Nile virus. The low toxicity of DEET compared to the danger of any of those diseases makes applying DEET to repel bugs a sensible choice, even in pregnant women.
Large, intentional overdoses of DEET by swallowing bug spray can be quite serious. How well a patient does depends on the amount and concentration of DEET swallowed and how quickly medical treatment is received. Seizures can lead to permanent brain damage and possibly death.
Borron SW. Pyrethrins, repellants, and other pesticides. In: Shannon MW, Borron SW, Burns MJ, eds. Haddad and Winchester's Clinical Management of Poisoning and Drug Overdose. 4th ed. Philadelphia, PA: Saunders Elsevier; 2007:chap 77.
Rhee JW. Pesticides. In: Marx JA, Hockberger RS, Walls RM, et al., eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 8th ed. Philadelphia, PA: Elsevier Mosby; 2013:chap 163.
Jacob L. Heller, MD, MHA, Emergency Medicine, Virginia Mason Medical Center, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.