what is the difference between ivermectin and avermectin

The Difference Between Ivermectin and Avermectin

Ivermectin and avermectin are both part of a class of medications known as antiparasitics, derived from the fermentation of the Streptomyces avermitilis bacterium. Although they share similarities and are often used interchangeably in conversation, there are distinct differences between the two that are crucial to understand in a medical and pharmaceutical context.

Origin and Composition

Avermectin was discovered in the late 1970s and is actually a group of compounds derived from the fermentation of the Streptomyces avermitilis organism. Avermectins are a complex of many different compounds, with avermectin B1a and avermectin B1b being the most studied. These compounds have potent antiparasitic properties and serve as the foundation for the development of precise medications.

Ivermectin, on the other hand, is a semi-synthetic derivative of avermectin, specifically developed to enhance its efficacy and safety profile. While it is based on the avermectin compounds, ivermectin has been chemically modified to improve its pharmacokinetic and pharmacodynamic properties, making it more effective and safer for use in humans and animals.

Both avermectin and ivermectin work through similar mechanisms. They target specific proteins in the nerve and muscle cells of parasites, leading to paralysis and death. This mechanism involves binding to glutamate-gated chloride channels (GluCl), which increases the permeability of the cell membrane to chloride ions. Ultimately, this disrupts the neuromuscular function of the parasites, making them unable to survive.

However, ivermectin is often preferred in clinical settings because its modifications allow for better absorption and distribution within the body. This results in prolonged activity against parasites and a broader spectrum of effectiveness, particularly in veterinary and human medicine.

Medical Applications

Ivermectin is widely recognized for its use in treating various parasitic infections in both humans and animals. In humans, it is primarily used to treat conditions such as onchocerciasis (river blindness), lymphatic filariasis, and strongyloidiasis. In veterinary medicine, ivermectin is utilized for a range of parasitic infections in pets and livestock.

Avermectin itself has limited use due to its inherent potency and toxicity. The focus has primarily been on ivermectin, as its safety profile has been well established through extensive clinical trials and real-world applications.

Safety and Side Effects

While both avermectin and ivermectin can cause side effects due to their mode of action, ivermectin has been studied more thoroughly regarding its safety profile. Common side effects of ivermectin may include dizziness, nausea, and mild skin rashes, but serious adverse reactions are rare when used as directed. Avermectin, due to its unrefined nature and higher potency, carries a higher risk of adverse effects, leading to its limited therapeutic use.

Conclusion

In summary, while ivermectin and avermectin are related, they are distinct in their chemical composition, mechanism of action, medical applications, and safety profiles. Ivermectin, being a semi-synthetic derivative of avermectin, presents a safer and more effective option for treating parasitic infections. Understanding the differences between these two compounds is essential for healthcare professionals and patients to ensure effective and safe treatment options for parasitic diseases.