How Viagra can help skin to heal
AGEL made from the anti-impotence drug Viagra ( sildenafil) could ease one of the main side- effects for cancer patients undergoing
radiotherapy.
Up to 85 per cent of those who have radiotherapy experience painful, red, or blistered skin around the area treated. The longer the treatment lasts, the worse this can be, as the same area of skin is exposed to radiation every day for up to two months. But now scientists have developed a water-based gel containing 5 per cent sildenafil, which, initial research suggests, helps to protect against and treat this damage.
In animal tests, radiation wounds healed quicker with the gel than without it.
Scientists say the drug helps by triggering the release of nitric oxide, a chemical known to play a vital part in wound healing by stimulating the flow of oxygen-rich blood to the damaged area. It does this in much the same way as it helps with impotence — by dilating tiny blood vessels so more blood can reach the affected region.
All wounds, burns and ulcers need a good supply of oxygen to heal.
About half of all cancer patients have some form of radiotherapy included in their treatment plan.
In some cases, it is given to shrink a tumour before surgery. In others, it is used afterwards to try to kill off any lingering cancer cells.
It is often effective, but can cause painful blistering of the skin, because radiotherapy, as well as destroying cancer cells, causes biochemical changes in healthy skin cells, leading to inflammation and breakdown.
Patients are advised to wash with unperfumed soap, pat skin dry instead of rubbing it, use moisturiser on the area and wear loose clothing to reduce irritation.
Dressings are sometimes used in between treatments to shield the area from everyday damage, and some patients are given steroid drugs to try to dampen down any inflammation. But even with such measures, it is estimated that more than 100,000 people a year in England alone experience skin problems from radiotherapy.
A team of scientists at the Institute of Nuclear Medicine & Allied Sciences, in New Delhi, India, decided to develop a Viagralike gel because previous studies had found that wounds in patients who had been given the drug for erectile dysfunction appeared to heal more rapidly.
The team devised a rub- on gel that was 95 per cent water and 5 per cent sildenafil.
In a study involving rats, scientists applied it daily for almost a month after radiotherapy treatment.
The results, published in December in the journal Burns, showed that skin damage was reduced by more than 80 per cent and wound contraction — the rate at which blisters and ulcers healed — increased by a similar amount.
Meanwhile, tensile strength — a measure of how strong the damaged skin is — was 45 per cent higher in the sildenafil group than in rats not treated with the new gel.
Dr Tom Roques, spokesman for the Royal College of Radiologists, said most NHS cancer patients experience only mild to moderate skin damage from radiotherapy.
He said: ‘ There is much more research needed before we know if this gel might be useful to any humans having radiotherapy.’