guys, thanks very much for the suggestions...
Sudafed is not available in greece under this name. So I went to the doctor and gave me a cortisone spray. It worked, but only for the course of the treatment. My nose is still a bit stuffed after I stopped the spray and I havent been diving to see any effect on sinus equalisation. I will also try to limit cow's products -I don't know if there is any scientific evidence but if you don't try on yourself you never know...

!! and wash nose with sea water.. I think it is very simple and effective suggestion
regards,
yiorgos