Mecamylamine may help to treat diabetic macular edema ......

We know that mecamylamine (see structure) has been used as a  ganglionic blocker in treating hypertension, but, like most ganglionic blockers, is more often used now as a research tool. It is also sometimes used as an anti-addictive drug to help people stop smoking tobacco, and is now more widely used for this application than it is for lowering blood pressure. This effect is thought to be due to it blocking α3β4 nicotinic receptors in the brain.

Now researchers from the Wilmer Eye Institute of Johns Hopkins University School of Medicine in Maryland have come up with an interesting finding from an early-stage human clinical trials. i.e.,  the drug  'mecamylamine'  was safe and had biological effects in a type of diabetic eye disease, and may offer researchers a new approach to prevent and treat diabetic macular edema. 

Diabetic macular edema is a complication of a specific region of the retina in the eye, called the macula, that develops when small blood vessels become leaky such that fluid accumulates. Without treatment, diabetic macular edema can cause vision impairment, blurriness, or blindness.

As per the claim by the researcers,  approximately 40% of the participants showed significant improvement in overall vision and/or the thickness of the retina. The treatment also showed biological effects in the retina indicating that the drug was able to gain access to the retinal vessels.

"The safety and early signals of treatment effect arising from this study may create a strong interest in the development of multiple treatment options that are affordable and can be self-administered, helping to ease the burden of healthcare delivery and compliance," said Barbara Araneo, Director of Complications Research for JDRF. ...

Ref : http://www.jdrf.org/index.cfm?fuseaction=home.viewPage&page_id=9065027A-1321-C844-137596CDA72C825B