Hydroxypropylmethylcellulose (HPMC)

Hydroxypropylmethylcellulose (HPMC), or hypromellose, is a cellulose-based ingredient used in tablets, eye drops and other products, and is the lubricating ingredient in some artificial tears for dry eye. This guide covers HPMC uses, how it works, dosage, side effects, precautions, drug interactions, use in pregnancy and breastfeeding and its approximate price in India.

At a Glance

What is Hydroxypropylmethylcellulose (HPMC)?

Hydroxypropylmethylcellulose (HPMC), or hypromellose, is used in oral, eye, nose and skin products. It is made from cellulose, a natural plant fiber, by chemical modification, so it is semisynthetic. It has two quite different roles, and it helps to keep them apart:

• As a pharmaceutical excipient (inactive ingredient): In tablets and capsules it helps shape the dosage form and can control how quickly the medicine is released. In this role HPMC does not treat the underlying disease. The active medicine does. It is also used to make plant-based (non-gelatin) capsule shells.
• As the active ingredient in some eye products: Hypromellose is the lubricating ingredient in certain artificial tears and eye gels used for dry eye.

It is not a conventional oral medicine.

How HPMC Works

• As a binder: It helps hold tablet ingredients together.
• As a film-former: It forms a smooth coating on tablets, which can make them easier to swallow.
• As a controlled-release agent: When a tablet containing high-viscosity HPMC meets fluid in the digestive tract, the HPMC swells into a gel layer. The medicine then moves out gradually through this gel, which delays release. The grade and amount of HPMC, other ingredients, and the pH of the fluid can all affect how fast the medicine is released.
• In eye products: It thickens the solution so it stays on the eye longer, which adds moisture and lubrication to the tear film. When it is the active ingredient, this lubrication is the intended effect. In other products it can serve as a thickening agent in the formulation.

Where HPMC Is Used

• Controlled-release medications: Used to make tablets and capsules that release their active medicine slowly over time.
• Ophthalmic preparations: Hypromellose is used in lubricating eye drops and gels for dry eye (as the active ingredient), and may also be used as a thickening agent in other eye formulations.
• Tablet coatings: Provides a smooth film coating on tablets, which can help with swallowing.
• Other uses: Tablet binder, suspending and thickening agent in some liquid medicines, plant-based capsule shells, and ingredient in some nasal and topical products.

HPMC Concentrations in Formulations (Not a Patient Dose)

HPMC does not have a dose that a patient takes or adjusts. The figures below are examples of ranges reported in pharmaceutical excipient references for particular formulation purposes. They vary by HPMC grade, product and manufacturer, they are not universal standards, and they are not therapeutic doses.

• Controlled-release matrix tablets and capsules: about 10% to 80% w/w, using high-viscosity grades
• Tablet binder: about 2% to 5% w/w
• Film-coating solutions: about 2% to 20% w/w in the coating solution
• Eye products, as a thickening agent in the formulation: about 0.45% to 1.0% w/w in some formulations
• Eye products, as the active lubricant: some over-the-counter products list hypromellose at about 0.2% or 0.3% as the active ingredient. Concentrations differ between products, so check the product label.

For eye drops, follow the product’s directions or your eye doctor’s advice. Do not use any HPMC product in place of a prescribed medicine.

Formulation note (for pharmacists and manufacturers): HPMC is incompatible with some oxidizing agents. This is a manufacturing consideration, not a patient precaution.

Side Effects of HPMC

• Oral medicines: As an excipient, HPMC is generally well tolerated. Side effects are usually due to the active medicine or other ingredients in the product, not HPMC itself.
• Eye products: Hypromellose-containing eye drops and gels may cause temporary irritation, discomfort, stinging, itching, eye pain or blurred vision, depending on the product. Other ingredients can also contribute, including preservatives such as benzalkonium chloride, which can irritate the eye, especially in dry eye or damaged corneas. Not every eye symptom is caused by hypromellose itself.

Stop using eye drops and see a doctor if you have eye pain, vision changes, continued redness or irritation, or if symptoms last more than 3 days or get worse.

HPMC Precautions

Eye products (follow the specific product label, as instructions can differ)

• Do not use if the solution changes color or becomes cloudy, or if you are sensitive to any ingredient.
• Do not touch the dropper tip to your eye or any surface, and replace the cap after use.
• If you wear soft contact lenses, check the label, because some products contain preservatives that can build up in lenses, and some products advise removing lenses before use.
• Seek medical advice for eye pain, vision changes, persistent redness or irritation, or worsening symptoms.

Oral controlled-release products:

• Do not crush, split or chew controlled-release tablets unless the label allows it, because this can disturb the release mechanism.

Using Multiple Eye Products

This is general administration advice, not an HPMC-specific drug interaction. If you use more than one eye drop or gel, many product instructions advise waiting several minutes (often 5 to 15 minutes) between products, and using a gel or thicker product last. The exact timing can differ between products, so follow the product label or your eye doctor’s directions.

HPMC Interactions With Medicines

HPMC in oral tablets and capsules is not usually the source of drug interactions. Interactions depend on the active medicine, so tell your doctor and pharmacist about all medicines you take.

HPMC in Pregnancy and Breastfeeding

• Hypromellose eye products: Systemic absorption is expected to be low, and some product labels note that data in pregnant women are limited. Product labeling can differ, so check the label of your specific product and talk to a healthcare professional if you are pregnant or breastfeeding.
• Oral medicines containing HPMC: Pregnancy and breastfeeding advice depends mainly on the active medicine and the complete formulation, not on HPMC as an excipient. Check with your doctor or pharmacist.

HPMC Brands, Strengths and Approximate Price in India

HPMC is mainly an excipient found in many tablets, capsules and eye products, so it does not have standalone medicine brands. The products below are examples of ophthalmic (eye) products containing hypromellose that may be marketed in India. They are not HPMC brands. The list is not exhaustive, availability can vary, and you should check locally.

Approximate price in India (listing-based): about ₹179–₹224 per 10 mL eye drop bottle, and about ₹460 for a 10 g gel tube, based on online pharmacy listings.

These are listing-based figures, not guaranteed current MRPs. Prices vary by brand, formulation and concentration, pack size, pharmacy and location, and availability can change. One listing showed Genteal as not available at the time.

How HealthPil Can Help

Questions about the role of excipients in a medicine are best answered by your pharmacist or doctor. If you have concerns about a medicine or eye product, you can consult a doctor or pharmacist through HealthPil, including for understanding what the ingredients in your medicines do.