Hyaluronic Acid (HA)

Hyaluronic Acid (HA) is a natural substance found within the human eye. HA is a natural polysaccharide that is found in the aqueous and vitreous humour. It is an ubiquitous component of the extracellular matrix. When introduced into the body, it is well tolerated with high water retention properties that reduce evaporation. It is an excellent natural eye lubricant which prevents damage to cells caused by physical stress. HA’s function in nature is to attract water and maintain a high level of hydration in cell tissue. HA attracts 3000 times its own weight in water i.e. 1 gram holds 6 litres of fluid.

HA has important bio-adhesive qualities; and has been shown to remain more effectively in the anterior eye and for a longer period of time, than Polyvinylpyrrolidone (PVP) and Poly Vinyl Alcohol (PVA). PVP and PVA are used in traditional dry eye formulations.

HA has a Non-Newtonian behaviour: it mimics the natural tear film in blinking. As friction increases, viscosity decreases (i.e. becomes more fluid).

Studies have shown an effect in the promotion of corneal epithelial wound healing. This effect may be due in part to the stimulating effect that HA has on epithelial cell proliferation. Other studies indicate that HA proceeds through a cell-surface HA receptor, but that it also appears to act as a physical barrier and/or scavenger of superoxide.

Tamarind Seed Polysaccharide (TSP)

Tamarind seed polysaccharide (TSP), or xyloglucan, is a naturally occurring, viscoelastic polymer - with good muco-adhesive properties, extracted from tamarind seeds with a similar structure to the ocular mucin. It is a viscosity enhancer with mucomimetic, muco-adhesive and bioadhesive activity that is devoid of ocular toxicity.

The “Best of both worlds”

Nuclear Magnetic Resonance (NMR) spectroscopy shows that the interaction between HA and TSP is co-operative. It involves HA acetyl groups & TSP internal glucose and galactose units. HydraMed has a higher capacity to encompass water when compared to each individual polymer. These characteristics are crucial for HydraMed’s properties of bioadhesion, biocompatibility and moisturising capacity. (1)

HydraMed – Helps improve the condition of the ocular surface

HydraMed mimics the non-Newtonian behaviour of natural tears, becoming less viscous during the blink and more viscous between blinks - minimising blurring immediately after instillation. It also demonstrates higher water absorption than the single polymers - maximising the essential properties of bioadhesivity, biocompatibility and moisturisation (1).

ROHTO® DRY EYE RELIEF restores the isotonic balance of the tears, helping to maintain the eyes’ natural health.