Identification

Name
Malathion
Accession Number
DB00772
Description

Malathion is a parasympathomimetic organophosphate compound that is used as an insecticide for the treatment of head lice. Malathion is an irreversible cholinesterase inhibitor and has low human toxicity.

Type
Small Molecule
Groups
Approved, Investigational
Structure
Thumb
Weight
Average: 330.358
Monoisotopic: 330.036066232
Chemical Formula
C10H19O6PS2
Synonyms
  • [(dimethoxyphosphinothioyl)thio]butanedioic acid diethyl ester
  • Carbophos
  • diethyl (dimethoxyphosphinothioylthio)succinate
  • Karbofos
  • Maldison
  • Mercaptothion
  • O,O-dimethyl S-(1,2-bis(ethoxycarbonyl)ethyl)
  • O,O-dimethyl S-(1,2-dicarbethoxyethyl) dithiophosphate
  • O,O-dimethyl S-(1,2-dicarbethoxyethyl)phosphorodithioate
  • O,O-dimethyl S-1,2-di(ethoxycarbamyl)ethyl
  • O,O-dimethyldithiophosphate diethylmercaptosuccinate
External IDs
  • ENT 17,034
  • ENT-17034
  • NSC-6524

Pharmacology

Indication

For patients infected with Pediculus humanus capitis (head lice and their ova) of the scalp hair.

Associated Conditions
Contraindications & Blackbox Warnings
Learn about our commercial Contraindications & Blackbox Warnings data.
Learn More
Pharmacodynamics

Malathion is an organophosphate insecticide commonly used to control mosquitos and other flying insects. Pharmaceutically, malathion is used to eliminate head lice. The principal toxicological effect of malathion is cholinesterase inhibition, due primarily to malaoxon and to phosphorus thionate impurities.

Mechanism of action

Malathion is a nonsystemic, wide-spectrum organophosphate insecticide. It inhibits acetylcholinesterase activity of most eukaryotes. Malathion is toxic to aquatic organisms, but has a relatively low toxicity for birds and mammals. The major metabolites of malathion are mono- and di-carboxylic acid derivatives, and malaoxon is a minor metabolite. However, it is malaoxon that is the strongest cholinesterase inhibitor. Cholinesterases catalyze the hydrolysis of the neurotransmitter acetylcholine into choline and acetic acid, a reaction necessary to allow a cholinergic neuron to return to its resting state after activation. Because of its essential function, chemicals that interfere with the action of cholinesterase are potent neurotoxins, causing muscle spasms and ultimately death.

TargetActionsOrganism
ACholinesterase
inhibitor
Humans
Absorption

Malathion in an acetone vehicle has been reported to be absorbed through normal human skin only to the extent of 8% of the applied dose. Absorption may be increased when malathion is applied to damaged skin. Malathion is rapidly and effectively absorbed by practically all routes including the gastrointestinal tract, skin, mucous membranes, and lungs. However, it is readily excreted in the urine, and does not accumulate in organs or tissues.

Volume of distribution
Not Available
Protein binding
Not Available
Metabolism

The major metabolites of malathion are the diacid and monoacid metabolites, namely, malathion dicarboxylic acid (DCA) and malathion monocarboxylic acid (MCA). Malaoxon, the active cholinesterase-inhibiting metabolite of malathion, is a minor metabolite. Both malathion and malaoxon are detoxified by carboxyesterases leading to polar, water-soluble compounds that are excreted.

Hover over products below to view reaction partners

Route of elimination
Not Available
Half-life

8-24 hours

Clearance
Not Available
Adverse Effects
Learn about our commercial Adverse Effects data.
Learn More
Toxicity

Malathion is slightly toxic via the oral route, with reported oral LD50 values of 1000 mg/kg to greater than 10,000 mg/kg in the rat. It is also slightly toxic via the dermal route, with reported dermal LD50 values of greater than 4000 mg/kg in rats. Moderate poisoning can result in chest tightness, difficulty breathing, bradycardia, tachycardia, tremor/ataxia, blurred vision, and confusion. Severe, life-threatening signs include coma, seizures, respiratory arrest, and paralysis. Malathion may also be irritating to the skin and eyes.

Affected organisms
  • Head lice
Pathways
Not Available
Pharmacogenomic Effects/ADRs
Not Available

Interactions

Drug Interactions
This information should not be interpreted without the help of a healthcare provider. If you believe you are experiencing an interaction, contact a healthcare provider immediately. The absence of an interaction does not necessarily mean no interactions exist.
DrugInteraction
AbametapirThe serum concentration of Malathion can be increased when it is combined with Abametapir.
DipyridamoleThe therapeutic efficacy of Malathion can be decreased when used in combination with Dipyridamole.
FluoxetineThe risk or severity of QTc prolongation can be increased when Fluoxetine is combined with Malathion.
HaloperidolThe risk or severity of QTc prolongation can be increased when Malathion is combined with Haloperidol.
HydroxyzineThe risk or severity of QTc prolongation can be increased when Malathion is combined with Hydroxyzine.
LefamulinLefamulin may increase the QTc-prolonging activities of Malathion.
PitolisantMalathion may increase the QTc-prolonging activities of Pitolisant.
TrazodoneThe risk or severity of QTc prolongation can be increased when Trazodone is combined with Malathion.
ZiprasidoneThe risk or severity of QTc prolongation can be increased when Malathion is combined with Ziprasidone.
Additional Data Available
  • Extended Description
    Extended Description

    Extended description of the mechanism of action and particular properties of each drug interaction.

    Learn more
  • Severity
    Severity

    A severity rating for each drug interaction, from minor to major.

    Learn more
  • Evidence Level
    Evidence Level

    A rating for the strength of the evidence supporting each drug interaction.

    Learn more
  • Action
    Action

    An effect category for each drug interaction. Know how this interaction affects the subject drug.

    Learn more
Food Interactions
No interactions found.

Products

International/Other Brands
Derbac-M (SSL) / Noury (Alfaco) / Prioderm (Norpharma)
Brand Name Prescription Products
NameDosageStrengthRouteLabellerMarketing StartMarketing EndRegionImage
MalathionLotion0.005 g/1mLTopicalTaro Pharmaceuticals U.S.A., Inc.2009-08-022020-01-17US flag
OvideLotion0.005 g/1mLTopicalTARO PHARMACEUTICALS USA, INC.1982-08-022020-01-17US flag
Additional Data Available
  • Application Number
    Application Number

    A unique ID assigned by the FDA when a product is submitted for approval by the labeller.

    Learn more
  • Product Code
    Product Code

    A governmentally-recognized ID which uniquely identifies the product within its regulatory market.

    Learn more
Generic Prescription Products
NameDosageStrengthRouteLabellerMarketing StartMarketing EndRegionImage
MalathionLotion0.005 g/1mLTopicalSuven Life Sciences Limited2014-02-20Not applicableUS flag
MalathionLotion0.005 g/1mLTopicalSynerx Pharma, Llc2010-03-052014-03-05US flag
MalathionLotion0.0005 g/1mLTopicalTaro Pharmaceuticals U.S.A., Inc.2014-01-31Not applicableUS flag
Malathion lotion, 0.5%Lotion5 mg/1mLTopicalKaralex Pharma, Llc, Woodcliff Lake, Nj 076772009-05-132009-05-13US flag
OvideLotion0.0005 g/1mLTopicalTaro Pharmaceuticals U.S.A., Inc.2014-01-31Not applicableUS flag
Additional Data Available
  • Application Number
    Application Number

    A unique ID assigned by the FDA when a product is submitted for approval by the labeller.

    Learn more
  • Product Code
    Product Code

    A governmentally-recognized ID which uniquely identifies the product within its regulatory market.

    Learn more

Categories

ATC Codes
P03AX03 — Malathion
Drug Categories
Chemical TaxonomyProvided by Classyfire
Description
This compound belongs to the class of organic compounds known as fatty acid esters. These are carboxylic ester derivatives of a fatty acid.
Kingdom
Organic compounds
Super Class
Lipids and lipid-like molecules
Class
Fatty Acyls
Sub Class
Fatty acid esters
Direct Parent
Fatty acid esters
Alternative Parents
Dithiophosphate S-esters / Dithiophosphate O-esters / Dicarboxylic acids and derivatives / Carboxylic acid esters / Sulfenyl compounds / Organothiophosphorus compounds / Organic oxides / Hydrocarbon derivatives / Carbonyl compounds
Substituents
Aliphatic acyclic compound / Carbonyl group / Carboxylic acid derivative / Carboxylic acid ester / Dicarboxylic acid or derivatives / Dithiophosphate o-ester / Dithiophosphate s-ester / Fatty acid ester / Hydrocarbon derivative / Organic dithiophosphate
Molecular Framework
Aliphatic acyclic compounds
External Descriptors
ethyl ester, diester, organic thiophosphate, carboxyalkyl phosphate (CHEBI:6651) / Organophosphorus insecticides (C07497) / a small molecule (CPD-13116)

Chemical Identifiers

UNII
U5N7SU872W
CAS number
121-75-5
InChI Key
JXSJBGJIGXNWCI-UHFFFAOYSA-N
InChI
InChI=1S/C10H19O6PS2/c1-5-15-9(11)7-8(10(12)16-6-2)19-17(18,13-3)14-4/h8H,5-7H2,1-4H3
IUPAC Name
1,4-diethyl 2-{[dimethoxy(sulfanylidene)-λ⁵-phosphanyl]sulfanyl}butanedioate
SMILES
CCOC(=O)CC(SP(=S)(OC)OC)C(=O)OCC

References

Synthesis Reference

Noel Rouy, Georges Gros, "Process for the preparation of malathion." U.S. Patent US4367180, issued August, 1969.

US4367180
General References
  1. Baker EL Jr, Warren M, Zack M, Dobbin RD, Miles JW, Miller S, Alderman L, Teeters WR: Epidemic malathion poisoning in Pakistan malaria workers. Lancet. 1978 Jan 7;1(8054):31-4. [PubMed:74508]
  2. Bonner MR, Coble J, Blair A, Beane Freeman LE, Hoppin JA, Sandler DP, Alavanja MC: Malathion exposure and the incidence of cancer in the agricultural health study. Am J Epidemiol. 2007 Nov 1;166(9):1023-34. Epub 2007 Aug 23. [PubMed:17720683]
  3. Edwards JW, Lee SG, Heath LM, Pisaniello DL: Worker exposure and a risk assessment of malathion and fenthion used in the control of Mediterranean fruit fly in South Australia. Environ Res. 2007 Jan;103(1):38-45. Epub 2006 Aug 17. [PubMed:16914134]
Human Metabolome Database
HMDB0014910
KEGG Drug
D00534
KEGG Compound
C07497
PubChem Compound
4004
PubChem Substance
46505287
ChemSpider
3864
BindingDB
85372
RxNav
6606
ChEBI
141474
ChEMBL
CHEMBL1200468
Therapeutic Targets Database
DAP000895
PharmGKB
PA164748092
RxList
RxList Drug Page
Drugs.com
Drugs.com Drug Page
Wikipedia
Malathion
FDA label
Download (133 KB)
MSDS
Download (57.9 KB)

Clinical Trials

Clinical Trials
PhaseStatusPurposeConditionsCount
3CompletedTreatmentHead Lice Infestation / Scabies1
3CompletedTreatmentLice Infestations4
2CompletedTreatmentHead Lice Infestation1
2, 3CompletedTreatmentLice Infestations1
1CompletedTreatmentLice Infestations1

Pharmacoeconomics

Manufacturers
  • Synerx pharma llc
  • Taro pharmaceuticals north america inc
Packagers
  • DPT Laboratories Ltd.
  • Karalex Pharmaceuticals
  • Medicis Pharmaceutical Co.
  • Taro Pharmaceuticals USA
Dosage Forms
FormRouteStrength
Shampoo
LotionTopical0.0005 g/1mL
LotionTopical0.005 g/1mL
LotionTopical5 mg/1mL
Prices
Unit descriptionCostUnit
Ovide 0.5% Lotion 59ml Bottle180.8USD bottle
Ovide 0.5% lotion2.95USD ml
Malathion 0.5% lotion2.65USD ml
DrugBank does not sell nor buy drugs. Pricing information is supplied for informational purposes only.
Patents
Patent NumberPediatric ExtensionApprovedExpires (estimated)Region
US7560445No2009-07-142027-02-01US flag
US7977324No2011-07-122026-08-14US flag
Additional Data Available
  • Filed On
    Filed On

    The date on which a patent was filed with the relevant government.

    Learn more

Properties

State
Liquid
Experimental Properties
PropertyValueSource
melting point (°C)2.8 °CPhysProp
boiling point (°C)156-157 °C at 7.00E-01 mm HgPhysProp
water solubility143 mg/L (at 20 °C)BOWMAN,BT & SANS,WW (1983)
logP2.36HANSCH,C ET AL. (1995)
Predicted Properties
PropertyValueSource
Water Solubility0.165 mg/mLALOGPS
logP2.67ALOGPS
logP1.86ChemAxon
logS-3.3ALOGPS
pKa (Strongest Basic)-6.8ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count2ChemAxon
Hydrogen Donor Count0ChemAxon
Polar Surface Area71.06 Å2ChemAxon
Rotatable Bond Count11ChemAxon
Refractivity78.18 m3·mol-1ChemAxon
Polarizability31.66 Å3ChemAxon
Number of Rings0ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Predicted ADMET Features
PropertyValueProbability
Human Intestinal Absorption+0.9031
Blood Brain Barrier+0.9236
Caco-2 permeable-0.5579
P-glycoprotein substrateNon-substrate0.7901
P-glycoprotein inhibitor INon-inhibitor0.6817
P-glycoprotein inhibitor IINon-inhibitor0.9522
Renal organic cation transporterNon-inhibitor0.9414
CYP450 2C9 substrateNon-substrate0.8308
CYP450 2D6 substrateNon-substrate0.9116
CYP450 3A4 substrateNon-substrate0.6132
CYP450 1A2 substrateNon-inhibitor0.8415
CYP450 2C9 inhibitorNon-inhibitor0.7963
CYP450 2D6 inhibitorNon-inhibitor0.9114
CYP450 2C19 inhibitorNon-inhibitor0.748
CYP450 3A4 inhibitorNon-inhibitor0.5673
CYP450 inhibitory promiscuityLow CYP Inhibitory Promiscuity0.8504
Ames testNon AMES toxic0.9132
CarcinogenicityCarcinogens 0.6261
BiodegradationNot ready biodegradable0.8429
Rat acute toxicity3.0259 LD50, mol/kg Not applicable
hERG inhibition (predictor I)Weak inhibitor0.9228
hERG inhibition (predictor II)Non-inhibitor0.8641
ADMET data is predicted using admetSAR, a free tool for evaluating chemical ADMET properties. (23092397)

Spectra

Mass Spec (NIST)
Download (10.5 KB)
Spectra
SpectrumSpectrum TypeSplash Key
Predicted GC-MS Spectrum - GC-MSPredicted GC-MSNot Available
Mass Spectrum (Electron Ionization)MSsplash10-004i-8900000000-c6bc16fae6e217410d40
Predicted MS/MS Spectrum - 10V, Positive (Annotated)Predicted LC-MS/MSNot Available
Predicted MS/MS Spectrum - 20V, Positive (Annotated)Predicted LC-MS/MSNot Available
Predicted MS/MS Spectrum - 40V, Positive (Annotated)Predicted LC-MS/MSNot Available
Predicted MS/MS Spectrum - 10V, Negative (Annotated)Predicted LC-MS/MSNot Available
Predicted MS/MS Spectrum - 20V, Negative (Annotated)Predicted LC-MS/MSNot Available
Predicted MS/MS Spectrum - 40V, Negative (Annotated)Predicted LC-MS/MSNot Available
1H NMR Spectrum1D NMRNot Applicable
13C NMR Spectrum1D NMRNot Applicable

Targets

Kind
Protein
Organism
Humans
Pharmacological action
Yes
Actions
Inhibitor
General Function
Identical protein binding
Specific Function
Esterase with broad substrate specificity. Contributes to the inactivation of the neurotransmitter acetylcholine. Can degrade neurotoxic organophosphate esters.
Gene Name
BCHE
Uniprot ID
P06276
Uniprot Name
Cholinesterase
Molecular Weight
68417.575 Da
References
  1. Overington JP, Al-Lazikani B, Hopkins AL: How many drug targets are there? Nat Rev Drug Discov. 2006 Dec;5(12):993-6. [PubMed:17139284]
  2. Imming P, Sinning C, Meyer A: Drugs, their targets and the nature and number of drug targets. Nat Rev Drug Discov. 2006 Oct;5(10):821-34. [PubMed:17016423]
  3. Ramos ZR, Fortunato JJ, Agostinho FR, Martins MR, Correa M, Schetinger MR, Dal-Pizzol F, Quevedo J: Influence of malathion on acetylcholinesterase activity in rats submitted to a forced swimming test. Neurotox Res. 2006 Jun;9(4):285-90. [PubMed:16782587]
  4. Ahmed M, Rocha JB, Mazzanti CM, Morsch AL, Cargnelutti D, Correa M, Loro V, Morsch VM, Schetinger MR: Malathion, carbofuran and paraquat inhibit Bungarus sindanus (krait) venom acetylcholinesterase and human serum butyrylcholinesterase in vitro. Ecotoxicology. 2007 May;16(4):363-9. Epub 2007 Mar 16. [PubMed:17364237]
  5. da Silva AP, Meotti FC, Santos AR, Farina M: Lactational exposure to malathion inhibits brain acetylcholinesterase in mice. Neurotoxicology. 2006 Dec;27(6):1101-5. Epub 2006 Apr 28. [PubMed:16716398]
  6. Berman HM, Westbrook J, Feng Z, Gilliland G, Bhat TN, Weissig H, Shindyalov IN, Bourne PE: The Protein Data Bank. Nucleic Acids Res. 2000 Jan 1;28(1):235-42. [PubMed:10592235]

Enzymes

Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
General Function
Oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen, reduced flavin or flavoprotein as one donor, and incorporation of one atom of oxygen
Specific Function
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally un...
Gene Name
CYP1A2
Uniprot ID
P05177
Uniprot Name
Cytochrome P450 1A2
Molecular Weight
58293.76 Da
References
  1. Buratti FM, D'Aniello A, Volpe MT, Meneguz A, Testai E: Malathion bioactivation in the human liver: the contribution of different cytochrome p450 isoforms. Drug Metab Dispos. 2005 Mar;33(3):295-302. Epub 2004 Nov 22. [PubMed:15557345]
  2. Malathion, Monograph [File]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
General Function
Steroid hydroxylase activity
Specific Function
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally un...
Gene Name
CYP2B6
Uniprot ID
P20813
Uniprot Name
Cytochrome P450 2B6
Molecular Weight
56277.81 Da
References
  1. Buratti FM, D'Aniello A, Volpe MT, Meneguz A, Testai E: Malathion bioactivation in the human liver: the contribution of different cytochrome p450 isoforms. Drug Metab Dispos. 2005 Mar;33(3):295-302. Epub 2004 Nov 22. [PubMed:15557345]

Drug created on June 13, 2005 07:24 / Updated on June 12, 2020 11:41

Logo pink
Are you a
new drug developer?
Contact us to learn more about our customized products and solutions.
Logo pink
Stay in the know!
As part of our commitment to providing the most up-to-date drug information, we will be releasing #DrugBankUpdates with our newly added curated drug pages.
#DrugBankUpdates