Snow Cyperdip

Indications

• Agricultural pest control
• Household insect control
• Vector control in public health

Dosage

Children: Not applicable; cypermethrin is not indicated for pediatric use.

Adults: Dosage varies based on formulation and application method; refer to specific product guidelines for detailed instructions.

Mechanism of action

Cypermethrin acts primarily on the voltage-sensitive sodium channels in the neurons of insects. It enhances the binding of specific radiolabeled toxins to these channels, leading to prolonged depolarization of the neuron and ultimately causing paralysis. Additionally, it may also interact with the gamma-aminobutyric acid receptor-chloride ionophore complex, further contributing to its neurotoxic effects.

Pharmacodynamics

The pharmacodynamic effects of cypermethrin involve its ability to interfere with normal nerve impulse transmission in insects. By altering the function of sodium channels, cypermethrin causes continuous nerve firing, leading to hyperexcitation, paralysis, and death of the target pest. Its selective toxicity allows for effective pest control with a relatively low risk to non-target organisms, including humans and other mammals.

Pharmacokinetics

Cypermethrin is absorbed through the cuticle of insects, where it readily penetrates the lipid membranes. It is lipophilic, which facilitates its rapid distribution within an organism. The compound is metabolized primarily in the liver, and its metabolites are excreted through urine and feces. The half-life of cypermethrin can vary based on environmental conditions and the specific formulation used.

Adverse effects

• Nausea
• Vomiting
• Dizziness
• Headache
• Skin irritation
• Respiratory distress
• Allergic reactions

Precautions

• Use with caution in individuals with a history of allergic reactions to pyrethroids
• Avoid contact with skin and eyes
• Use protective clothing and equipment when handling
• Keep out of reach of children and pets

Pregnancy

Safety during pregnancy has not been established. Use only if clearly needed.

Breast-feeding

It is unknown whether cypermethrin is excreted in human milk. Caution is advised.

Storage

Store in a cool, dry place, away from direct sunlight and heat sources. Keep container tightly closed.

Formulations

• Emulsifiable concentrate
• Aerosol
• Granules
• Dusts

Mechanism of action

Pyrethroid insecticides are synthetic neurotoxins patterned after the naturally occurring pyrethrins. Their mechanism of action is thought to involve effects primarily at the voltage-sensitive sodium channel of both insect & mammalian neurons, although recent studies have raised the possibility that these cmpds may also act at the gamma-aminobutyric acid receptor-chloride ionophore complex. Here we show that active pyrethroids of the alpha-cyano-3-phenoxybenzyl class allosterically enhance the binding of (3)H-batrachotoxinin-A 20-alpha-benzoate to voltage-sensitive sodium channels of rat brain in a dose-dependent & stereospecific manner. Comparison of the rank order of potency for enhancement of (3)H-batrachotoxinin-A 20-alpha-benzoate binding & insecticidal activity in a series of toxic steroisomers of cypermethrin, representative of the class, reveals a correlation between the two measures. These results support a sodium channel site model for pyrethroid action & suggest a useful & practical method to help evaluate the relationship between the sodium channel & insecticidal potency for members of this class of cmpds. Following absorption through the chitinous exoskeleton of arthropods, pyrethrins stimulate the nervous system, apparently by competitively interfering with cationic conductances in the lipid layer of nerve cells, thereby blocking nerve impulse transmissions. Paralysis and death follow. /Pyrethrins/ The efforts of this study were directed at defining the importance of esterases, mixed function oxidases and mitochondrial respiratory chain enzymes in in vitro covalent binding of cismethrin and the two cyanopyrethroids, cypermethrin and deltamethrin to phenobarbital induced rat liver homogenate and microsomes. Each enzyme system was selectively inhibited to elucidate the activation mechanism involved. Piperonyl-butoxide and carbon-monoxide were used to inhibit mixed function oxidases. Tetraethylpyrophosphate inhibited esterase and trichloropropene-oxide inhibited epoxide-hydrolase. Potassium cyanide or rotenone was used to block the mitochondrial electron transport. The study demonstrated that covalent binding of cismethrin, cypermethrin, and deltamethrin was dependent on pyrethroid concentration. Inhibition of esterases and mitochondrial respiration only slightly altered the covalent binding level. Inhibition of cytochrome p450 and mixed function oxidases reduced the covalent binding, making it almost nonexistent. The covalent binding was decreased by 50% through an 80% inhibition of epoxide-hydrolase. In vitro, the comparison of data between alcohol and acid labeling of the same pyrethroid suggested that the whole molecule was bound to proteins in an activation process, perhaps epoxidation, and that hydrolysis could only occur afterwards. The role of cytochrome p450 dependent monooxygenases in the covalent binding process was stressed. Interaction with sodium channels is not the only mechanism of action proposed for the pyrethroids. Their effects on the CNS have led various workers to suggest actions via antagonism of gamma-aminobutyric acid (GABA)-mediated inhibition, modulation of nicotinic cholinergic transmission, enhancement of noradrenaline release, or actions on calcium ions. Since neurotransmitter specific pharmacological agents offer only poor or partial protection against poisoning, it is unlikely that one of these effects represents the primary mechanism of action of the pyrethroids, & most neurotransmitter release is secondary to incr sodium entry. /Pyrethroids/ For more Mechanism of Action (Complete) data for CYPERMETHRIN (12 total), please visit the HSDB record page.