Diosmin

Drug

Diosmin is a semisynthetic flavonoid molecule derived from citrus d (modified hesperidin). It is an oral phlebotropic drug used in the treatment of venous disease, i.e., chronic venous insufficiency (CVI) including spider and varicose veins, leg swelling (edema), stasis dermatitis and venous ulcers. It is also used as a stand-alone or surgical adjunctive therapy in hemorrhoidal disease (HD).

There are extensive clinical trials that show diosmin improves all stages of venous disease including venous ulcers and improves quality of life. There are no prospective studies in arterial disease.

Diosmin is currently a prescription medication in some European countries (under the Dio-PP, Venotec, Daflon etc. tradenames), and is sold as a nutritional supplement in the United States.

Diosmin has been found to be effective in mitigating hyperglycemia in diabetic rats. It is also speculated that diosmin might have potential in the treatment of neurodegenerative diseases, such as Alzheimer's disease, and its anti-inflammatory and anti-apoptotic activity has been demonstrated in neuronal cells, in vitro.

Mechanisms

Diosmin prolongs the vasoconstrictor effect of norepinephrine on the vein wall, increasing venous tone, and therefore reducing venous capacitance, distensibility, and stasis. This increases the venous return and reduces venous hyperpressure present in patients suffering from CVI.

Diosmin improves lymphatic drainage by increasing the frequency and intensity of lymphatic contractions, and by increasing the total number of functional lymphatic capillaries. Furthermore, diosmin with hesperidine decreases the diameter of lymphatic capillaries and the intralymphatic pressure.

At the microcirculation level, diosmin reduces capillary hyperpermeability and increases capillary resistance by protecting the microcirculation from damaging processes.

Diosmin reduces the expression of endothelial adhesion molecules (ICAM1, VCAM1), and inhibits the adhesion, migration, and activation of leukocytes at the capillary level. This leads to a reduction in the release of inflammatory mediators, principally oxygen free radicals and prostaglandins (PGE2, PGF2a).

Regulatory status

Diosmin is distributed in the U.S. as a dietary supplement and as a prescription medical food. The FDA concluded that there was inadequate evidence on which to base an expectation of safety., however, diosmin products have beed used in Europe for over 40 years with no safety issues. One company that markets diosmin supplements, Nutratech, has responded that diosmin can reasonably be expected to be safe on the basis of clinical trials, and has a long history of use in Europe. In the U.S., dietary supplements are regulated under Dietary Supplement Health and Education Act of 1994, which does not require proof of efficacy so long as no specific health claims are made. The enhanced version of diosmin, Vasculera, is sold as a medical food product. Under FDA regulation, medical food products must obtain GRAS (generally recognized as safe) status and have scientifically proven efficacy.