Hydroxypropyl methylcellulose (HPMC) is widely used in tablet coating. As a common pharmaceutical excipient, it has many functions and advantages.
Film-forming material: HPMC is one of the commonly used film-forming materials in film coating formulations. It has good film-forming properties, suitable film strength, transparent coating layer, and is not easy to crack. It is relatively stable under light, heat and certain humidity, and is soluble in organic solvents and water. It has little adverse effect on the disintegration and dissolution of tablets. Therefore, it is a widely used gastric soluble coating material with good film coating effect.
Protect API: HPMC coating can protect active pharmaceutical ingredients (API) from environmental factors such as light, oxidation and moisture, ensuring that the drug can continue to play its intended role even after being stored for a considerable period of time.
Control drug release: Through film coating, drug manufacturers can control the release site, rate and time of API. This is very important for some drugs that need to be released with a delay, or for drugs that must release a constant amount of API within a specific period of time.
Improve patient compliance: Film-coated tablets are easier to take, which can improve patient compliance.
Improve tablet appearance: Film coating can provide a smooth surface and bright colors, enhance brand recognition and patient medication experience.
As a binder and disintegrant: HPMC can also be used as a binder. Its low viscosity HPMC solution can effectively reduce the contact angle of the drug, which is conducive to the wetting of the drug. The expansion coefficient after absorbing water can reach hundreds of times, which can significantly improve the disintegration and dissolution release rate of the drug.
Improve tablet stability: HPMC has low hygroscopicity, which can be used as an advantage because it can reduce the stability problems caused by moisture absorption during storage of tablets.
As a sustained-release skeleton material: In sustained-release preparations, HPMC can be used as a hydrophilic skeleton material. By adjusting the viscosity and dosage of HPMC, the release rate of the drug can be controlled to achieve a sustained-release effect of the drug.
Improve solubility: HPMC ethanol solution or aqueous solution is used as a wetting agent for granulation, which is effective in improving the solubility of tablets.
Improve coating quality: As a film-forming material, HPMC has the biggest advantage over other film-forming materials in that it is water-soluble, does not require organic solvents, and is safe and convenient to operate. HPMC also has a variety of viscosity specifications. If used properly, the quality and appearance of the coated tablets are better than other materials.
HPMC is widely used in tablet coating, which can not only improve the quality and appearance of tablets, but also effectively protect drug ingredients, control drug release, and improve patient compliance.