Food additives Europe numbers: E464
Hypromellose is an artificial, semi-synthetic, non-digestible polysaccharide used as an ophthalmic lubricant, a food additive and for other pharmaceutical purposes. It is a derivative of cellulose, obtained from plant sources, and is a polymeric mixture of anhydroglucose units. It is used as a thickening agent, suspending agent, emulsifying agent, lubricant, and as an adhesive. Hypromellose is used as an ocular lubricant to prevent further irritation, to relieve dryness of the eye, and to protect the eye from further damage. It is also used as a food additive to improve the texture of food products, to stabilize emulsions, and to bind ingredients together. In the pharmaceutical industry, it is used to coat tablets and to provide a release coating.
Hypromellose, also known by the longer name hydroxypropyl methylcellulose (HPMC), is a versatile substance with several applications in medicine. Here's a breakdown of its key uses:
1. Eye Lubricant (Artificial Tears):
- This is the most common use of hypromellose in medicine.
- It acts as a lubricant for the eye, mimicking the natural tears and relieving dryness, irritation, and discomfort.
- Hypromellose helps retain moisture in the eye by forming a protective layer over the cornea (the clear front part of the eye).
- It's available as eye drops or ointments, often sold under brand names.
2. Controlled-Release Drug Delivery:
- Hypromellose plays a crucial role in formulating many oral medications.
- Due to its thickening and gelling properties, it's used as a binder or coating agent in tablets and capsules.
- This allows for controlled release of the medication into the body.
- Hypromellose can be formulated to release the drug slowly over time, extending its therapeutic effect and potentially reducing dosing frequency.
3. Other Medical Uses:
- Hypromellose may be used in certain laxatives to bulk up stool and promote bowel movements.
- It can also be found in some nasal sprays or throat lozenges as a thickening or soothing agent.
Key Points about Hypromellose:
- Generally considered safe and well-tolerated.
- Eye drops containing hypromellose may cause temporary blurred vision upon application.
- Hypromellose is an inactive ingredient and doesn't have any direct medicinal effects itself.
In summary:
Hypromellose is a valuable substance in medicine, primarily used as an eye lubricant and as a tool for controlled drug delivery in oral medications. Its thickening and gelling properties make it beneficial for various pharmaceutical applications.