II. Epidemiology

  1. DEET used by 200 Million persons worldwide
  2. Used by 38% of U.S. population
  3. Only 30 adverse events reported between 1966-1997

III. Indications

  1. Prevention of Vector-borne Infection in endemic areas
  2. Prevention of Insect Bite

IV. Mechanism

  1. DEET concentration above 10% lasts longer, not better
  2. Insect Repellents work as a chemical barrier
    1. Block Mosquito's detection of prey

V. Adverse Effects (DEET)

  1. General
    1. Concentration >15% associated with adverse effects
    2. Most DEET preparations safe
  2. Local Effects
    1. Mild skin irritation
    2. Corneal irritation
    3. Mucosal irritation
  3. Serious effects with excessive use under Occlusion
    1. Neurologic
      1. CNS Depression
      2. Seizures
    2. Cardiovascular
      1. Hypotension
      2. Tachycardia
  4. Other effects: Gastrointestinal
    1. Nausea and Vomiting with ingestion

VI. Efficacy

  1. DEET is effective against Mosquitoes, ticks, lice, fleas

VII. Technique

  1. Apply every 1-2 hours during exposure
  2. Apply Sunscreen before (under) Insect Repellent
  3. Do not apply repellent around eyes and mouth
  4. Concentration up to 30% may be used in pregnancy and over age 2 months

VIII. Preparations

  1. DEET concentration affects duration of activity, not the effectiveness
    1. Duration 2 hours: 6% DEET
    2. Duration 2-3 hours: 10% DEET
    3. Duration 3-5 hours: 20% DEET
    4. Duration 5-6 hours: 30% DEET
    5. DEET concentration above 50% offers no benefit over lower concentration, but raise toxicity risk
  2. Longest acting and most effective agents
    1. Ultrathon (34% DEET): 12 hour protection claimed
    2. Deep Woods Off (23% DEET): 200-360 minutes protection
    3. Sawyer Controlled Release (20% DEET): 180-325 minutes
      1. Slowly releases DEET in response to sweating
      2. Lower toxicity due to slow release
    4. Off Skintastic (6.6% DEET): 90-170 minutes protection
  3. Moderate duration of activity and effectiveness
    1. Avoid combined Insect Repellent with Sunscreen (Sunscreen needs more frequent application)
    2. Bite Blocker Kids (2% Soybean oil): 16-195 minutes
    3. Off Kids Skintastic (4.75% DEET): 45-120 minutes
    4. Skin-So-Soft Bug Guard Plus (7.5% IR3535): 10-60 min
  4. Shortest duration and minimal activity (<5 to 20 minutes)
    1. Citronella (avoid; 10% lasts 20 minutes)
      1. Natrapel
      2. Herbal Armor
      3. Green Ban for People
      4. Buzz Away
      5. Skin-So-Soft Bug Guard
      6. Skin-So-Soft Moisturizing Suncare
    2. Wrist Bands (ineffective, avoid)
      1. Gone Original Wristband (9.5% DEET)
      2. Repello Wristband (9.5% DEET)
      3. Gone Plus Repelling Wristband (Citronella)
  5. Alternatives to DEET with similar efficacy to DEET 10 to 15%
    1. Nootkatone (sesquiterpenoid)
      1. Pending release in 2022
    2. Insect Repellent 3535 (Ethyl butylacetylaminopropionate)
    3. Picaridin 7 to 10% (e.g. Cutter Advanced, Natrapel)
      1. Less irritation and better smell and feel than DEET
      2. Duration of effect is 2 hours
      3. Safe in pregnancy and children down to 2 months of age (at concentration 10% or less)
    4. Lemon Eucalyptus Oil 30% (e.g. Repel Plant Based)
      1. Active ingredient is para-menthane-3,8-diol
      2. Do not use in children under age 3 years (not studied)
      3. Appears as effective as 15% DEET for Mosquito protection, but unclear if it protects against ticks

IX. Precautions

  1. Limit DEET concentration to less than 30 to 35%
  2. CDC recommends DEET 35% for Malaria prevention
  3. Avoid supplements (e.g. B Vitamins, Garlic) for Insect Bite protection (ineffective)

X. Management of toxicity

  1. Skin Decontamination
  2. Seizure management with Benzodiazepines
  3. Supportive management

XI. References

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Related Studies

Ontology: Deet (C0011134)

Definition (MSH) A compound used as a topical insect repellent that may cause irritation to eyes and mucous membranes, but not to the skin.
Concepts Hazardous or Poisonous Substance (T131) , Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH D003671
SnomedCT 15414003, 16968005
English DET, Deet, DETA, N,N Diethyl m toluamide, N,N Diethyltoluamide, N,N-Diethyl-m-toluamide, N,N-Diethyltoluamide, Benzamide, N,N-diethyl-3-methyl-, N,N Diethyl 3 methylbenzamide, N,N-Diethyl-3-methylbenzamide, DEET [Chemical/Ingredient], det, deta, deet, deets, diethyl toluamide, DEET, diethyltoluamide, Diethyl toluamide (substance), Diethyl toluamide, DIETHYLTOLUAMIDE, Diethyltoluamide, Diethyltoluamide (substance), DEET N,N-DIETHYL-META-TOLUAMIDE
Swedish Deet
Czech DEET
Finnish DEET
Russian DIIT, DIT, ДИИТ, ДИТ
Japanese ジエチルトルアミド, デート(防虫剤), デタミド, ディート, メタデルフェン, ジエルタミド, フリペル
French DEET, N,N-Diéthyl-m-toluamide, N,N-Diéthyl-méta-toluamide
Italian N,N-dietil-3-metilbenzamide, N,N-dietiltoluamide, N,N-dietil-m-toluamide, DEET
Polish DEET
Spanish dietilotoluamida, deet, dietilotoluamida (sustancia), N,N-dietil-metatoluamida, N,N-dietil-m-toluamida, N,N-dietil-meta-toluamida, Dietiltoluamida, N,N-dietil-3-metilbenzamida, dietiltoluamida (sustancia), dietiltoluamida, DEET
Portuguese N,N-dietil-3-metilbenzamida, N,N-dietil-meta-toluamida, N,N-dietil-metatoluamida, N,N-dietil-m-toluamida, Benzamida, N,N-dietil-3-metil-, Dietiltoluamida, DEET
German DEET

Ontology: Insect Repellents (C0021572)

Definition (MSH) Substances causing insects to turn away from them or reject them as food.
Concepts Hazardous or Poisonous Substance (T131)
MSH D007302
SnomedCT 75627006
English Insect Repellents, Repellents, Insect, insect repellent, insect repellents, insect repellant, insect repellants, Insect repellant, Insect repellent (substance), Insect repellent, Insect repellent, NOS
French Agents insectifuges, Produits insectifuges, Insectifuges
Swedish Insektsavvisande medel
Czech hmyzí repelencia
Finnish Hyönteiskarkotteet
Russian REPELLENTY, SREDSTVA, OTPUGIVAIUSHCHIE NASEKOMYKH, РЕПЕЛЛЕНТЫ, СРЕДСТВА, ОТПУГИВАЮЩИЕ НАСЕКОМЫХ
Polish Repelenty
Spanish repelente de insectos (sustancia), repelente de insectos, Repelentes de Insectos
German Insektenrepellents
Italian Insettorepellenti
Portuguese Repelentes de Insetos

Ontology: Citronella oil (C0172379)

Definition (NCI) The essential oil extracted from the leaves and stems of various Cymbopogon species. Citronella oil is used for its aromatic properties in parfumary, cosmetics, candles and soaps, and as an insect repellant.
Concepts Lipid (T119) , Pharmacologic Substance (T121)
MSH C076730
SnomedCT 12358005
English citronella oil, CITRONELLA OIL [VA Product], CITRONELLA OIL@@MISCELL@OIL (ML), CITRONELLA OIL MISCELL OIL (ML), Citronella Oil Oil, Citronella oil, CITRONELLA OIL, Citronella Oil, CITRONELLA OIL MISC. OIL, CITRONELLA OIL OIL, CITRONELLA OIL @ @ OIL, Citronella oil (substance)
Spanish aceite de citronela (sustancia), aceite de citronela

Ontology: Mosquito repellant (C0729417)

Concepts Hazardous or Poisonous Substance (T131)
SnomedCT 311901004
English mosquito repellant, mosquito repellants, Mosquito repellant, Mosquito repellant (substance)
Spanish repelente de mosquitos (sustancia), repelente de mosquitos

Ontology: picaridin (C1437018)

Concepts Organic Chemical (T109) , Hazardous or Poisonous Substance (T131)
MSH C483506
SnomedCT 416559004
English ICARIDIN, 1-(1-Methylpropoxycarbonyl)-2-(2-hydroxyethyl)piperidine, 1-Methylpropyl 2-(2-hydroxyethyl)-1-piperidinecarboxylate, Icaridin, Picaridin (substance), Picaridin, 1-(1-methylpropoxycarbonyl)-2-(2-hydroxyethyl)piperidine, 2-(2-hydroxyethyl)-1-piperidinecarboxylic acid 1-methylpropyl ester, picaridin, sec-butyl 2-(2-hydroxyethyl)piperidine-1-carboxylate
Spanish picaridina (sustancia), picaridina