Hydroxypropyl methylcellulose (commonly referred to as HPMC) is a chemically modified cellulose polymer that is off-white in color and considered safe for human consumption. It is most commonly used as an alternative to gelatin and gluten in vegan-friendly products.
- Alternative to Gelatin: It serves as an alternative to gelatin because of its vegetarian source and its physical similarities to gelatin. This is extremely useful if you need to make your own supplements since it can help vegetarians and those with dietary restrictions consume supplements and medications.
- Alternative to Gluten: It is also a very good replacement for gluten in gluten-free food. In baking bread, it limits “both the diffusion and the loss of water from the bread crumb and the interactions between starch and protein macromolecules,” which results in softer gluten-free bread and reduces staleness during storage.
- Other uses: It acts as a thickening agent, coating polymer, binder, and bioadhesive in pharmaceutical, food, and industrial manufacturing.
- This medication is an insert that is placed in your eye to treat dry eyes. It is usually used when an artificial tears solution is not successful. This medication may also be used to treat certain other eye disorders (keratitis, decreased corneal sensitivity). It works by keeping the eye moist, helping to protect the eye from injury and infection and to decrease symptoms of dry eyes such as burning, itching, and feeling as if something is in the eye.
- In an FDA study with rats, there were no significant toxic effects other than growth retardation once HPMC reached levels of 20 to 30% of the rats’ diet. This study noted that growth retardation may be contributed to malnutrition and not the amount of HPMC. In another study, rabbits were injected with 2% HPMC for over a month and there were no observations of toxicity or irritation. Overall, the FDA sees it as a non-toxic and non-irritating inactive ingredient that is safe for human use and consumption.
Source: Labdoor, https://labdoor.com/article/what-is-hydroxypropyl-methylcellulose