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.

The majority of bug repellents contain DEET (N,N-diethyl-m-toluamide) as their active ingredient. It is one of the few insect repellants that work. DEET 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 non-toxic, but it can cause breathing problems if large doses are inhaled.

Bug sprays, or insect repellants, are sold under various brand names.

For pyrethrins:

• Breathing difficulty
• Coughing
• 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
• Vomiting

For DEET:

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
• Nausea
• Vomiting

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 that 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.

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

The health care provider will measure and monitor the patient's vital signs, including temperature, pulse, breathing rate, and blood pressure. Symptoms will be treated as appropriate. The patient may receive:

• Activated charcoal
• Breathing tube
• Bronchoscopy -- camera down the throat to see burns in the airways and lungs
• Fluids through a vein (IV)
• Oxygen
• 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

For pyrethrins:

Severe asphyxiation can be rapidly life-threatening. For simple exposure or inhalation of small amounts, recovery should occur.

For DEET:

When used as directed in low doses, DEET is relatively nonharmful. It is the preferred bug repellant for the prevention of mosquito born 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.