Parkinson’s Treatment May Help Macular Degeneration

Sometimes there is a crossover in the conventional pharmaceutical world. Just ask all those benefitting from the billion dollar erectile dysfunction drug Viagra (Sildenafil), which was originally used to treat hypertension.

It looks like another may be added to the list. The Parkinson’s drug, levodopa (L-dopa), is showing some promise in combating the debilitating eye disease called macular degeneration.

Your Magnificent Macula

You may take your vision for granted, not understanding its unique mechanics.

The macula is an integral part of your sight, made up of millions of light sensing cells that create central vision. It is the middle operating system between what you see and how it is instantaneously delivered to the brain where the image is formed.

When the macula is damaged, central vision can become distorted, blurry, dark and sometimes destroyed. According to the National Eye Institute, smoking, race (mostly caucasians) and family history all play a major role in the development of this disease.

Macular degeneration has been reported as the most common cause of blindness in people over age 50 however it can present earlier in some. It is estimated that approximately 1.8 million people suffer from this disease.

The Find

The natural brain chemical dopamine is the main target when treating Parkinson’s as this disease robs people of this essential chemical resulting in many symptoms, including muscular malfunction. Levodopa enables the brain to produce more dopamine and slow the disease which currently has no cure.

It turns out that dopamine is a major player in assisting healthy functioning of the retina. Researchers realized this and decided to create a study to find a possible crossover link to treating macular degeneration.

In the Lab

The research did not consist of a handful of patients but rather a large demographic through personal interaction and database information.

Lead author of the study that linked levodopa to macular degeneration, Brian McKay a research associate professor in ophthalmology and vision science at the University of Arizona comments,

”Rather than looking at what might cause AMD, we instead wondered why certain people are protected from AMD. This approach had never been done before.” (Medical News Today – MNT)

US News reports on the specifics,

“For the study, researchers analyzed medical records of 37,000 patients from a Wisconsin clinic. The researchers looked for signs whether or not those who took levodopa had lower rates of age-related macular degeneration. They also examined a medical database of 87 million people. The researchers found that diagnosis of age-related macular degeneration occurred, in general, around age 71. But among those who took levodopa, it occurred much later, at around age 79.”

From these statistics, it is theorized that the Parkinson’s drug may be affecting photoreceptors in the eye. These are neurons that assist the eye in sensing all forms of light and macular degeneration significantly dulls its ability to function.

Preventing Progression

More good news is on the horizon with these findings which show that taking levodopa may decrease the dangerous transition from dry macular degeneration to the dangerous wet macular degeneration. Wet degeneration is when the “abnormal blood vessels leak fluid or blood into the macula region, resulting in rapid central vision loss.” (MNT)

Stay Informed

Now don’t go running to your doctor demanding levodopa at the first sign of vision blurriness. This study is the first of many that will determine the exact dosages and expected results. Talk to your doctor and ophthalmologist first to determine if you have symptoms and then stay informed.

Other news for macular degeneration include:

• Blood Pressure Meds – Longstanding research known as the Beaver Dam Eye Study looked at how high blood pressure medication (vasodilators and oral beta blockers) affected vision. It was found that these meds could create a higher risk for developing macular degeneration.

• Nano-Eye Drops – “Researchers at University College London (U.K.) recently reported the results of animal studies that demonstrate it’s possible to create formulations of tiny nano-particles loaded with the anti-VEGF drug Avastin [macular degeneration drug exclusively delivered via injections into the eye] and deliver significant concentrations of the drug to the back of the eye by means of topical eye drops.” (All About Vision)

• Wear Good Sunglasses – “…research confirms results of earlier studies that show a high lifetime exposure to UV radiation increases the risk of cataracts and macular degeneration.” (AAV)

Hopefully, as more research emerges, macular degeneration will be less of a threat to vision health.