contact lens, contact lens medication

Contact Lenses Are Newest Way to Absorb Medication

July 23, 2009 03:00 PM
by Haley A. Lovett
Scientists say they have developed a contact lens that can deliver eye medication evenly over a 30-day period, adding one new method of drug delivery to an ever-growing list.

Medicated Lenses May Help Glaucoma and Dry Eye Sufferers in Future

The drug-dispensing contact lenses have been in development for nearly a decade, according to Hadley Leggett of This new version, scientists claim, has solved the problem of being able to deliver a steady amount of medication over a long period of time. The latest lens design holds the drug inside, much like a pocket.

For sufferers of glaucoma, dry eyes and eye infections, the medicated lenses may help solve the problem of remembering to take your eye medication or eye drops, and it may also help solve the inconsistency in drug delivery from eye drops. According to Leggett, although most eye medication is taken via drops, studies have found that only 1 to 7 percent of the medication is actually absorbed by the eye, with the rest falling down the cheek or down the back of the throat.

The contact lenses are still in development and will need to undergo more lab testing before they will be up for consideration by the FDA.

Background: Traditional methods of treating glaucoma; Latisse

The conditions that cause glaucoma result in damage to one’s optic nerve, and can eventually lead to blindness. According to the Mayo Clinic, the cause of glaucoma is usually increased pressure inside the eye. Tests at your eye doctor can help to catch glaucoma in an early stage, and treatment can delay or prevent the progression of vision loss.

Traditional treatments include eye drops and oral medications designed to help prevent the build up of liquid (and thus pressure) in your inner eye. For more advanced glaucoma or for patients that don't respond to other medication, surgery to relieve eye pressure may be required.

Lumigan, a medication prescribed for glaucoma patients, was found to promote eyelash growth. In late 2008, the FDA approved the cosmetic use of Lumigan, to be marketed under the name Latisse, as an eyelash enhancer.

Related Topic: Medicated skin patches; How drugs enter the bloodstream

The new drug-delivering contact lenses might seem similar to the skin patches (known as transdermal patches) that have been on the market for years. According to MSN Encarta, some of the most common medicines delivered through skin patches are those for chest pain, for nicotine cessation, for hormone replacement therapy and for the prevention of motion sickness. More recently, transdermal patches have been used for hormonal contraceptive delivery and to treat ADHD.

Using a patch to deliver medication might be easier for some than remembering to take a daily pill, but not all drugs can be effectively absorbed by the bloodstream by all methods of delivery. HowStuffWorks explains the different drug delivery methods (pills, inhalants, shots, IVs, suppositories, eye or ear drops, and dermal patches) and how each works to deliver drugs to the bloodstream. For example, patches are only effective if the medication can migrate successfully through the skin, and some drugs cannot be taken as pills because the acidity of your stomach may affect the medication.

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