ADVOCATE (FOR DOGS) SOLUTION

Indications

• Control of fleas in dogs and cats
• Control of lice infestations
• Agricultural pest management for crops

Dosage

Children: Refer to the BNF for Children for paediatric dosage guidelines.

Adults: Refer to the BNF for specific dosage recommendations based on the formulation and condition being treated.

Mechanism of action

Imidacloprid acts as a selective agonist at nicotinic acetylcholine receptors (nAChRs), causing continuous stimulation of the receptors, leading to paralysis and death in insects. This agonistic action disrupts the normal transmission of nerve impulses, resulting in neurotoxicity. Its selectivity for insect nAChRs over mammalian receptors accounts for its relative safety in higher organisms.

Pharmacodynamics

The pharmacodynamic profile of imidacloprid is characterized by its neurotoxic effects on insects, leading to rapid onset of paralysis and death. The drug’s efficacy is influenced by its ability to bind to specific receptor subtypes in insects, leading to prolonged exposure of the synaptic cleft to acetylcholine. This results in persistent stimulation of the postsynaptic neuron and eventual insect mortality.

Pharmacokinetics

Imidacloprid exhibits good absorption through the cuticle of insects and is widely distributed in tissues. It has a half-life that can vary significantly depending on the environmental conditions and formulation but is generally in the range of a few hours to several days. The elimination of imidacloprid occurs primarily via metabolic pathways, with the liver being a primary site of metabolism in mammals, while in insects, it undergoes hydrolysis and other metabolic processes.

Pregnancy

There are no adequate and well-controlled studies in pregnant women. Imidacloprid should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

It is not known whether imidacloprid is excreted in human milk. Caution should be exercised when administering to nursing women.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Indications

• Onchocerciasis
• River blindness

Dosage

Children: Refer to the BNF for Children for specific dosing guidelines.

Adults: Refer to the BNF for specific dosing guidelines.

Mechanism of action

Moxidectin selectively binds to the parasite's GABA-A and glutamate-gated chloride ion channels, essential for the functioning of invertebrate nerve and muscle cells. This binding increases the permeability of the cell membranes, allowing an influx of chloride ions, which results in flaccid paralysis of the parasite without directly killing it.

Pharmacodynamics

Moxidectin has shown remarkable efficacy against _Onchocerca volvulus_, demonstrating a superior ability to reduce microfilarial loads in infected individuals compared to ivermectin. The administration of moxidectin leads to a significant decrease in microfilariae levels to undetectable amounts, making it suitable for mass drug administration, while maintaining safety.

Pharmacokinetics

Moxidectin is well absorbed after oral administration with a long half-life, allowing for less frequent dosing compared to other treatments. Its pharmacokinetic profile supports its use in mass treatment strategies for onchocerciasis, although specific parameters such as absorption rate, distribution volume, and elimination route require detailed clinical studies for comprehensive understanding.

Pregnancy

There are no adequate data from the use of moxidectin in pregnant women. Use only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

It is unknown whether moxidectin is excreted in human breast milk. Caution should be exercised when moxidectin is administered to a nursing woman.

Storage

Store in a cool, dry place, away from direct sunlight. Keep out of reach of children.

Mechanism of action

Moxidectin selectively binds to the parasite's GABA-A and glutamate-gated chloride ion channels which are vital for the function of invertebrate nerve and muscle cells. It presents activity against the parasite but it does not kill him. Once moxidectin is bound, there is an increased permeability leading to an influx of chloride ions and flaccid paralysis of the parasite.

Pharmacodynamics

Moxidectin has been reported to be highly effective against _Onchocerca volvulus_ when compared to ivermectin. When moxidectin was administered in infected individuals, the microfilarial load in the skin was lower even when compared to the current therapy, ivermectin. The levels of microfilarial got reduced to an undetectable level while being safe to be used in mass drug administration.