It’s Buggin’ Me! How to Safely Use an Insect Repellent
Medically reviewed on May 8, 2018 by L. Anderson, PharmD.
Why Should I Use an Insect Repellent?
The use of insect repellents is a safe and effective way to prevent insect and tick-borne diseases.
Mosquito bites can lead to:
while the small deer tick can cause Lyme disease.
The U.S. Centers for Disease Control (CDC) strongly recommends the use of insect repellents to prevent transmission of West Nile virus and other mosquito-borne diseases. Most cases of malaria diagnosed in the U.S. originate from other parts of the world.
How Do Insect Repellents Work?
Many insects like mosquitoes are attracted to the host because of their skin odors and carbon dioxide from their breath.
Repellents contain an ingredient that makes the person 'unattractive' for biting; however, repellents do not kill the insect. Repellents are effective only at short distances from the treated surface, so the user may still see mosquitoes flying nearby.
In the warmer months it is important to use an insect repellent; in tropical climates it may be needed year-round.
How Should I Apply an Insect Repellent?
Applying your insect repellent is not just a random spray here and there. Apply repellents only when you are planning to be outdoors and only to exposed skin - not under clothing.
Wash the treated skin with soap and water when you return indoors, especially if applied repeatedly throughout the day. Do not apply insect repellents directly to open wounds, and avoid spraying directly onto the face; instead spray on your hand and rub onto your face.
Choose a repellent that provides protection for the amount of time that you will be outdoors. Only apply repellents outside to help avoid breathing in the spray.
If you do get a bite or sting, follow these suggestions.
How Else Can I Protect Myself From Insects?
You can apply insect repellents containing DEET or permethrin to your clothing; however, DEET may stain clothing. Sprays containing permethrin are available specifically for clothes, insect nets, sleeping bags, shoes, and boots; do not apply permethrin directly to your skin.
You can also limit the time spent outdoors, especially at the peak mosquito-feeding times of dawn and dusk. However, most Zika virus infections are transmitted via mosquito bites particularly from the day-time active Aedes species of mosquito.
Are Insect Repellents Safe?
The U.S. Center for Disease Control and Prevention (CDC) recommends using products that have been shown to be effective in clinical trials and that contain active ingredients registered with the Environmental Protection Agency (EPA) for use as insect repellents on skin or clothing.
These repellents include:
- DEET 20%: duration of 8-12 hours (like Cutter Backwoods and Off! Deep Woods)
- Picaridin for skin: duration of up to 8 hours (also known as KBR 3023, Bayrepel, and icaridin)
- IR3535: duration of 4 to 8 hours
- 2-Undecanone: duration of 2 to 4 hours (methyl nonyl ketone)
- Oil of lemon eucalyptus (OLE) for use in those 3 years and older: duration up to 6 hours
Permethrin for clothing and gear only (not for skin application) has also been suggested.
An EPA registered insect repellent is not expected to cause serious side effects to humans or the environment when used according to the directions.
When used as directed, these insect repellents are proven safe and effective even for women who are pregnant or breastfeeding.
What is DEET?
DEET, or N, N-diethyl-m-toluamide, has the best documented repellent effectiveness. DEET is active against mosquitoes, ticks, chiggers, fleas, and some flies. DEET concentrations range from 5% to 100%, but concentrations greater than 30% have not been shown to be more effective.
A long-acting formula is available that contains 34% DEET (Ultrathon lotion) and affords 6 to 12 hours of protection. Other retail brands names that contain DEET include Off, Cutter, and Sawyer.
The Aedes genus of mosquito, known to transmit Zika, Yellow Fever, dengue, and chikungunya, are not always repelled by the widely used insect repellent DEET, as they cannot smell the DEET.
Is DEET Safe for Children or Infants?
The CDC states that insect repellents like DEET are safe for children and infants older than 2 months, and the American Academy of Pediatrics notes that repellents should contain no more than 10% to 30% DEET (look for N,N-diethyl-m-toluamide on the spray bottle) when used in children. Higher concentrations will last longer.
Avoid prolonged, excessive use or internal consumption; brain injury has occurred in these situations.
No serious illness has been linked to the use of DEET in children when used according to manufacturer’s recommendations. However, once inside the house, it is best to wash repellent off with soap and water.
How Should I Apply an Insect Repellent on a Child?
Parents should choose a repellent based on the amount of outdoor time, mosquito exposure, and risk of mosquito-transmitted disease in the area.
Important points to remember:
- apply repellent to your own hands, then rub onto the child
- avoid the child's eyes, mouth, and use sparingly around ears
- avoid open wounds
- do not apply repellent under clothing
- wash treated clothing
- wash the treated skin when you have returned indoors
- keep repellents out of reach of children
Can Pregnant or Breastfeeding Women Use Insect Repellents?
Yes, according to the Centers for Disease Control and Prevention (CDC).
In pregnant or breastfeeding women, the CDC states that DEET, picaridin, IR3535, oil of lemon eucalyptus or 2-undecanone are proven safe and effective.
As always, contact your healthcare provider for answers to questions about the use of any medication in pregnancy or breastfeeding and follow label directions.
What About Zika Virus?
Most people don't even know they've been infected by a mosquito if they get Zika virus.
Common symptoms of Zika include:
- joint pain
- conjunctivitis (red eyes)
But for pregnant women, it's important to avoid a bite from the Aedes species of mosquito. Zika virus can also be spread by sexual contact, so condom use is important. Zika virus can be passed from a pregnant woman to her fetus, and infection during pregnancy can cause a serious birth defect of the brain called microcephaly.
Women who are pregnant should not travel to areas with Zika. If you must travel to one of these areas or if you live in an area with Zika, talk to your doctor or other healthcare provider and strictly follow steps to prevent mosquito bites and to prevent sexual transmission.
CDC has updated news and guidelines for Zika virus and which travel areas to avoid on their website.
Is Picaridin Also an Effective Insect Repellent?
Picaridin, also known as KBR 3023, is available in 5% to 20% concentrations and is an effective repellent for flies, mosquitoes, chiggers, ticks.
One study has shown the 19% concentration of picaridin is as effective as the Ultrathon brand of DEET lotion. An advantage of picaridin over DEET is that it does not damage plastic or fabric.
Various brand names are available in spray and wipes for application to the skin. Brands that contain picaridin include Cutter and Advanced Natrapel.
Are There Any Natural Insect Repellents?
OLE, or Oil of Lemon Eucalyptus (p-menthane 3, 8-diol) is a plant-based repellent and is registered with the EPA.
In studies evaluating malaria, OLE provides 6 hours of protection against mosquitoes. OLE should NOT be used in children under 3 years of age.
When OLE was compared to DEET for effectiveness against mosquitoes found in the U.S., OLE provided similar protection to lower concentrations of DEET.
OLE products include Repel Lemon Eucalyptus and Cutter Lemon Eucalyptus. Some consumers complain of the OLE odor.
Is Avon's <i>Skin So Soft</i> a Bug Repellent?
IR3535, found in some Skin So Soft products, is available in various strengths and is sold in combination with a sunscreen. CDC does not recommend using the combination products because the sunscreen will need to be applied more often than the repellent. Some studies have questioned the effectiveness of the 7.5 percent concentration of IR3535.
IR3535 is available as a lotion and a spray. Products that contain IR3535 include:
- Avon's Skin So Soft Bug Guard Plus
- Bull Frog Mosquito Coast.
Can I Spray Repellent On My Clothes for Added Protection?
Permethrin is intended for application to clothing and gear, but NOT directly to the skin.
Permethrin is a synthetic pyrethroid contact insecticide that can be used on clothing, mosquito nets, tents and sleeping bags for protection against mosquitoes and ticks. It remains active for several weeks, even through multiple launderings.
Permethrin is available as a spray for clothes, insect nets, sleeping bags, shoes, and boots.
One brand is Sawyer Premium Permethrin Clothing Insect Repellent. Follow label directions for timelines for re-application.
What Are the Common Side Effects With Insect Repellents?
Serious side effects to insect repellents are extremely rare if the product is used as directed.
Skin reactions due to allergy and eye irritation are the most common reactions.
If you suspect you are having a skin reaction, do this:
- stop use of the product
- wash the area with soap and water
- call 911 or contact the National Poison Control Center at 1-800-222-1222
- if the repellent gets into your eyes, flush your eyes with water immediately and contact 911 or the Poison Control Center.
Can I Apply DEET and a Sunscreen at the Same Time?
Yes, but apply the sunscreen first, then the repellent and follow the instructions for each product.
When applying a product that combines both a sunscreen and a repellent in the same bottle, it may be necessary to reapply a sunscreen separately because it will need to be reapplied more frequently than the repellent.
Keep in mind that reapplying the combination product too often may lead to toxic effects due to the repellent. Swimming or sweating may lessen the effective time of these products, and reapplication may be needed. Always follow package directions.
See additional CDC recommendations on Insect Repellent Use & Safety
Finished: It’s Buggin’ Me! How to Safely Use an Insect Repellent
- CDC. West Nile Virus. Accessed May 8, 2018. https://www.cdc.gov/westnile/index.html
- CDC. West Nile Virus. Insect Repellent Use and Safety. Accessed May 8, 2018. https://www.cdc.gov/westnile/faq/repellent.html
- Illinois Department of Public Health. Prevention and Control. DEET Insect Repellents. Accessed May 8, 2018 at http://www.idph.state.il.us/envhealth/deetfacts.htm
- Fradin MS, Day JF. Comparative efficacy of insect repellents against mosquito bites. N Engl J Med. 2002; 347:13-8.
- Insect Repellents. The Medical Letter. Vol 54 (1399). September 17, 2012. Accessed May 8, 2018.
- Hurricane Katrina: Information on Insect Repellent Use and Safety in Children. Drugs.com. Accessed May 8, 2018 at: https://www.drugs.com/news/hurricane-katrina-insect-repellent-safety-children-1533.html
- Bug Spray Poisoning. Drugs.com. Accessed May 8, 2018 at https://www.drugs.com/enc/bug-spray-poisoning.html
- CDC. West Nile Virus. Questions and Answers. West Nile Virus Fact Sheet. Accessed May 8, 2018 at https://www.cdc.gov/westnile/resources/pdfs/wnvFactsheet_508.pdf
- American Academy of Pediatrics. HealthyChildren.org. Choosing an Insect Repellent for Your Child. Accessed May 8, 2018 https://www.healthychildren.org/English/safety-prevention/at-play/Pages/Insect-Repellents.aspx