Ethyl nicotinate is an organic compound found in various products, from sweet oranges to cosmetics. It is an ester derived from nicotinic acid, also known as niacin or vitamin B3. This compound is recognized for its distinctive sweet and somewhat fruity odor. Ethyl nicotinate is synthesized through a chemical reaction between nicotinic acid and ethanol, often aided by an acid catalyst.
Understanding Ethyl Nicotinate
Ethyl nicotinate is classified as a pyridinecarboxylic acid, containing a pyridine ring with a carboxylic acid group. Its chemical formula is C9H9NO2, and it appears as a clear, colorless to yellow liquid. It is soluble in water and considered a strong basic compound based on its pKa. It has a boiling point ranging from 223 to 224 °C and a density of 1.107 g/mL at 25 °C.
How Ethyl Nicotinate Works
Ethyl nicotinate’s primary mechanism of action, especially in topical applications, is vasodilation, the widening of blood vessels. When applied to the skin, it interacts with G protein-coupled receptor 109A (GPR109A) in dermal Langerhans cells. This activation increases arachidonic acid and produces prostaglandins like prostaglandin D2 (PGD2) and prostaglandin E2 (PGE2). These prostaglandins activate receptors on capillaries, expanding blood vessels.
This process results in the “niacin flush.” The flush manifests as temporary redness, warmth, and sometimes a tingling or itching sensation on the skin in the treated area. The effects are localized; only the applied skin experiences these changes. Vasodilation improves blood flow, contributing to perceived benefits in various applications.
Where Ethyl Nicotinate is Used
Ethyl nicotinate is incorporated into topical formulations across several industries due to its vasodilatory properties. In the cosmetics sector, it is used in anti-aging and firming creams. The increased blood circulation it promotes can lead to a temporary plumping effect on the skin and enhance the absorption of other beneficial ingredients.
Sports creams and muscle warm-up products also utilize ethyl nicotinate. Its ability to increase blood flow to muscles can help in pre-exercise warm-up routines and aid in post-exercise recovery by facilitating the removal of waste products and delivery of nutrients. Some specialized medical creams for conditions like sprains, muscle pains, and tendonitis may include ethyl nicotinate at concentrations of 1% to 2%, to leverage its local vasodilatory effects for temporary relief and improved circulation in the affected area.
Potential Side Effects and Precautions
The most common side effect of topically applied ethyl nicotinate is the “niacin flush,” characterized by temporary redness, warmth, and sometimes itching or tingling sensations. This reaction is a normal physiological response to the vasodilation it causes and subsides within 30 to 90 minutes. It is important to differentiate this flush from a true allergic reaction, which might present with more severe symptoms like urticaria or swelling.
To minimize risks, perform a patch test before widespread use of products containing ethyl nicotinate. This involves applying a small amount to an inconspicuous skin area and observing for adverse reactions over 24 to 48 hours. Avoiding application on sensitive or broken skin is recommended, as this can intensify the flushing sensation or lead to irritation. If extreme pain, prolonged irritation, or signs of a severe allergic reaction occur, discontinue use and consult a healthcare professional.