Гвайфенезин

Описание

Guaifenesin is an oral expectorant drug. The expectorant action of guaifenesin is mediated by stimulation of the gastrointestinal tract. It is a common ingredient in prescription and over-the-counter medications used to treat cough due to colds and minor upper respiratory infections. Additionally, Guaifenesin is also a centrally-acting muscle relaxant and is used routinely in combination with analgesics and sedatives in large-animal veterinary surgery.

Химические свойства

This substance is a white crystalline powder with a melting point of 78.5-79°C and a boiling point of 215°C (2.53kPa). It is soluble in 20ml of water and ethanol, chloroform, glycerin, and dimethylformamide. It is easily soluble in benzene but insoluble in petroleum ether. It has a slightly bitter taste and a slightly particular odor.

Использование

Guaifenesin is a muscle relaxant with expectorant properties often used as an expectorant to facilitate the removal of phlegm from the airways in acute respiratory tract infections. Guaifenesin comes in tablet and capsule form, as syrup, as dissolving granules, and recently as an extended-release (longacting) tablet. The tablets, capsules, dissolving granules, and syrup are usually taken with or without food every 4 h as needed. The extended-release tablet is usually taken with or without food every 12 h.

Общее описание

Guaifenesin is an expectorant, widely used in the treatment of cough. Its mode of action involves the alleviating of cough discomfort by increasing sputum volume and decreasing its viscosity, thus resulting in effective cough.
Pharmaceutical secondary standards for application in quality control, provide pharma laboratories and manufacturers with a convenient and cost-effective alternative to the preparation of in-house working standards.

Механизм действия

Guaiphenesin facilitates secretion from bronchial mucous membranes, thus relieving a cough in colds, bronchitis, and bronchial asthma.

Экологическая судьба

Guaifenesin’s production and use as veterinary and human medicines may result in its release to the environment through various waste streams.
If released to air, an estimated vapor pressure of 1.5× 10–6 mm Hg at 25 ℃ indicates that guaifenesin will exist in both the vapor and particulate phase.
Based upon an estimated Henry’s law constant of 4.4 × 10^-11 atm-m³ mol^-1, volatilization from moist soil surfaces or from water surfaces are not expected to be important fate processes for guaifenesin.
Guaifenesin is expected to have high mobility in soil based upon an organic carbon–water partition coefficient (Koc) of 140, which indicates that it will have more solubility in water and is less likely to adsorb onto organic matter in soil and plants.

использованная литература

[1] Peter V. Dicpinigaitis and Yvonne E. Gayle, Effect of Guaifenesin on Cough Reflex Sensitivity, 2003, vol. 124, 2178-2181 DOI:10.1378/CHEST.124.6.2178
[2] Leonid Kagan, Eran Lavy and Ammon Hoffmann, Effect of mode of administration on guaifenesin pharmacokinetics and expectorant action in the rat model, Pulmonary Pharmacology & Therapeutics, 2009, vol. 22, 260-265 DOI:10.1016/j.pupt.2008.12.020
[3] Sittig's Pharmaceutical Manufacturing Encyclopedia
[4] Synthesis of Essential Drugs (2006, Elsevier)
[5] Plumb's Veterinary Drug Handbook
[6] https://pubchem.ncbi.nlm.nih.gov/compound/Guaifenesin